Physics

Enzymes, which are catalysts, are found in the human digestive system. Predict the most likely effect on human digestion if a particular enzyme was in short supply.

Particular food molecules would digest more slowly.

A penny rolls off a 0.9-m high table with a horizontal velocity of 0.35 m/s. How long does it take the penny to hit the ground?

0.4 s

A proton is initially moving with a constant velocity. When the proton approaches the ______ of another proton ahead of it, it slows down.

electric field

Convert 7525 grams to kilograms.

7.525 kg

What are frames of reference?

coordinate systems used to describe objects' motion

Which of the following elements can take part in a nuclear fission reaction?

thorium

In an isobaric process at 580,000 Pa, the volume of an ideal gas changes from 0.0055 m3 to 0.0085 m3. What is the work done during this expansion?

1,700 J

If the object below is in equilibrium, what is the value of the unknown force?

16N

The voltage in a particular circuit is 100.0 V. The current in the circuit is 25 A. What is the resistance?

4.0

Ethanol evaporates readily at room temperature. Why is it a main ingredient in liquid perfume?

Evaporating ethanol moves freely and spreads out, carrying fragrance molecules with it.

What does it mean for one substance to be warmer than another?

It has more average thermal energy.

Which Lewis dot structure represents the same element as this schematic of an atom's electron configuration?

N (5 dots) match valence electron #

Nuclear power plants use control rods to prevent

None of the listed answers are correct

A boy sits motionless partway down a playground slide. The force of friction balances the force of gravity. A girl hands the boy a book. Why does the boy still not move?

The force of friction and the force due to gravity increase together. Friction and gravity are still balanced.

Observe the following mechanical waves with amplitudes as shown. Wave A transmits energy in 6 s, and Wave B transmits energy in 4 s. How does the power transmitted by Wave A compare with that of Wave B?

Wave A transmits six times as much power as Wave B.

A joule is equivalent to

a newton meter

What is the shape of a projectile's trajectory?

a parabola

The thermal energy transferred during a calorimetry experiment is equal to 32 J. This is equivalent to the work done by a 2-N force

acting over a distance of 16 m

Two elements are both silver gray metals at room temperature. One element's atomic number is 8 more than the other's. They are both very reactive with water and have similar melting and boiling points. On the periodic table, these elements are most likely found

adjacent in the same column

The moon is attracted to Earth by the force of gravity. This causes

an acceleration directed toward the center of Earth

Which mass ratio is similar to the ratio of the mass of an electron to the mass of a proton?

dime:bowling ball

Ultrasound uses which of the following types of waves?

high-frequency sound waves

If a process remains at constant temperature, then the corresponding graph of the process on a PV diagram will be

hyperbolic

In their liquid states, the molecules and atoms of a substance are ________ closely packed than in a solid and can move _______ freely than in a gaseous state.

less; less

What would you get if you split a bar magnet in the middle?

two magnets, each with its own north and south poles

Which of the following is a common technology used in motion sensors?

ultrasonic sound pulses

If the current through one light bulb is i, what is the current through the other light bulb?

i, because current constant in series

As the mass of an object increases, the force of gravity

increases

If an object has constant speed, then its velocity

may be constant

In physics, work is defined as

the process of applying a force through some distance

From the structure of the atom, it can be concluded that

the range of the electromagnetic force is greater than the size of the nucleus

An 87-kg object travels at 22 m/s west. It collides head-on with a second object traveling 12 m/s east. After the collision, both objects are at rest. Calculate the mass of the second object.

160 kg

Predict the result of adding charge to an insulator.

A static charge builds up

The following chemical equation represents a reaction involving propane (C3H8): Which of the following is an appropriate conclusion to draw about this chemical reaction?

There is more energy stored in the bonds of the reactants.

In what ways are bosons similar to quarks?

They are both subatomic particles.

In an adiabatic process, the internal energy of a system decreases by 34,000 J. What is the work done by the system?

34,000 J

These are illustrations of objects moving in counterclockwise circular paths. Which is the best illustration of a tangential acceleration vector?

B

What is a key feature of particles in a plasma state?

Many of the particles are ionized.

A particular internal combustion engine in a car turns 30% of the potential energy in its gas tank into useful mechanical work to power the car. The engine is an example of a(n)

irreversible process because the lost energy cannot be recovered

An astronaut in outer space whirls a ball on a string in a circle at constant speed. The ball

is constantly accelerating

The gravitational attraction between a large object and a small object

is greater than the attraction between two small objects the same distance apart

Explain why sound energy is not a type of potential energy.

It does not depend on the position or configuration of the system.

A ball is rolling across the floor at a constant speed. What will happen to the ball if it is exposed to an unbalanced force in the same direction that it is moving?

Its speed will increase.

In the ionic bond between sodium and chlorine,

a valence electron is transferred from one atom to another

Calculate the magnitude of the gravitational force for two masses, 150.0 kg and 100.0 kg, 0.020 meters apart.

0.0025 N

A grasshopper jumps and accelerates at 4.5 m/s2. If its legs exert a force of 0.062 N during the jump, what is the mass of the grasshopper?

0.014 kg

A wave emitted from a source has a frequency of 10 Hz and wavelength 2.5 m. How much time will it take to reach a person located 5 m from the source?

0.2

A worker is melting samples of various metals. Which sample will require the most heating to melt?

2 kg of nickel

A football is thrown vertically with an initial velocity of 33 m/s. Calculate the velocity of the ball when its height has increased by 5 m.

31 m/s

How long would a 700-W microwave have to run to use the same energy as a 100-W light bulb left on for 35 min?

5min

If no new carbon-14 was formed in Earth's atmosphere, which of the following would be a likely consequence?

Carbon-14 dating would not be possible.

Which of the following statements about a closed system are true?

Matter cannot enter the system AND any thermodynamic process can occur within the closed system.

A classmate wonders whether her cell phone emits a strong magnetic field. Which of the following investigations could help answer this question?

Measure the current in a piece of copper wire placed near the phone as the phone is turned on and off.

Two speedboats are racing on the ocean. The crew on each boat is listening for a whistle from a person on the beach. When the whistle sounds, each crew observes a different-pitched sound. Which of the following could have caused this?

One boat is moving toward the beach, while the other is moving away from the beach.

A car suddenly slams on its brakes and skids west for 8 m before stopping. The force of friction acting on the car was directed

east

A transverse wave is traveling north. In which directions could the wave oscillate?

east-west

A bucket of water is spun in a circle by a string attached to the handle of the bucket. If the string is 1 m long, what is the maximum possible displacement of the bucket from its starting position during two complete revolutions?

2 m

A 5-kg object is pushed across a floor with a force of 30 N to the right. It accelerates at 2 m/s2. What was the force of friction with the floor?

20 N to the left

What is the missing isotope in the following radioactive decay process? 219/86RN ---> A/ZX + 4/2He

215/84Po

Two reactants A and B react very slowly without a catalyst. When a particular positive catalyst C is introduced, A and B react quickly. What would happen if a negative catalyst, D, was used instead of C?

A and B would react more slowly.

Which of the following statements about specific heat is true?

A substance with high specific heat resists changes in temperature more than a substance with low specific heat.

Of the following, how do features of electric field diagrams and magnetic field diagrams differ?

Electric forces are aligned with their field vectors, but magnetic forces are not.

The four forces found in the universe are the gravitational force, the strong nuclear force, the weak nuclear force, and the _____.

Electromagnetic Force

Carbon is found in Earth's atmosphere as carbon dioxide (CO2). Which is the most likely reason for measured levels of atmospheric carbon dioxide in the Northern Hemisphere cycle in this graph?

During the summer season, photosynthesis in plants uses more carbon dioxide.

Two masses are separated by a distance r. The force of attraction between the two masses is F. If the size of one mass is doubled, how does F change?

F is doubled.

If you halve the distance between two masses of 100 kg each, what happens to the gravitational force?

F is multiplied by 4.

A friend claims that throwing a baseball up towards the school roof illustrates gravitational potential energy transforming into kinetic energy. What is wrong with your friend's statement?

Gravitational potential energy transforms into kinetic energy when an object falls.

The ionization energy of an atom is the energy required to remove one electron from the atom. According to the periodic table, which group of elements releases its electrons most easily?

Groups 1 and 2

Carbon forms the "backbone" of many molecules that include other elements. Why does not hydrogen form the "backbone" of molecules?

Hydrogen is able to fill its valence shell when forming just a single bond.

Momentum is usually not exactly conserved in a real world demonstration of momentum conservation. What is a possible reason for this fact?

Net external forces act on the system.

Which physical law most directly describes the motions of objects that are acted on by forces?

Newton's second law of motion

Which of the following statements about Newton's second law is false?

Objects with a small inertia are harder to accelerate than objects with a large inertia.

Which diagram is an incomplete circuit diagram?

One with big ole gap in it

Two chemical reactions, A and B, start at the same time. Reaction B occurs at a lower temperature and finishes first. If the same two reactions are repeated, but the temperature of Reaction B is raised to the same level as Reaction A, then what is true about the second round of reactions?

Reaction B happens more quickly.

The number protons in a particular atom decreases, resulting in a new element. Which of the following conclusions can be drawn?

The atomic nucleus has undergone decay.

A hammer strikes a train track 100 m from two people. One person has her ear to the train track, and the other person is listening to the air. Who will hear the sound of the hammer first?

The person listening to the train tracks will hear the sound first.

How can the photoelectric effect be explained based on the wave theory of light?

The photoelectric effect cannot be explained by the wave theory of light.

How could the position data from a motion sensor be used to create a velocity--time graph?

The rate of change in the position between any two moments in time can be calculated using position data.

A satellite travels through deep space with a constant velocity. Suddenly a small asteroid strikes the satellite head-on. Describe what happens to the satellite's momentum.

The satellite's momentum decreases.

Which of the following is a difference between visible light waves and X rays?

X rays can pass through materials that visible light cannot.

When someone presses down on a surface and the surface does not move they have not done any work. However, the person will still have _______.

applied a force

A mass of 250 kg is 25 m apart from a second mass of 300 kg. If the distance is increased to 50 m, which of the following is most likely the new gravitational force between them?

approximately one-fourth of the original force

Under which two circumstances are Newton's laws the least applicable?

at very small scales and at very high speeds

Which particle has a typical diameter of about 0.3 nm (3 × 10-10 m)?

atom

In which case are Newton's laws NOT valid?

for a moving object inside a train that is rounding a bend

A fisherman is watching water waves ripple past his boat. How could he determine the wavelength of the water waves?

measure the distance between consecutive waves

Which kind of mathematical calculations are most useful in determining the components of a vector in two perpendicular directions when only the angle of the resultant vector is known?

sine and cosine

An object is in circular motion. What can directly change the magnitude of its velocity?

tangential acceleration

A student pushes a chair into a desk. If the student's push is the action force, then what is the reaction force in this example of Newton's third law?

the force from the chair on the student

A person is trying to solve the equation for the energy of a light wave: E = hc/ λ . She knows the values of h and c. What does the quantity λ represent?

wavelength

Which of the following is true about the electrical forces between atoms?

The electrons from one atom will attract the protons from a nearby atom.

Based on Newton's first law of motion, which of the following describes the action of an unbalanced force on a car?

a car that is braking

For which object's motion will Newton's laws give the least accurate prediction?

an electron orbiting a massive nucleus

Which of the following best explains why an explosive charge in a cannon can cause a cannonball to fly out of the cannon with a high velocity?

because chemical potential energy can convert to kinetic energy

Suppose all but two switches are closed. Which pair of switches, if left open, will cause a short circuit?

#4 and #6

Analyze the following wave. Which line segment represents the wavelength of the wave?

C

If the magnitude of a force acting on an object is known, what represents the magnitude in a free body diagram?

the length of the arrow

An isotope of platinum is shown. Which of the following changes would result in the isotope osmium-186?

the loss of 2 protons and 2 neutrons

Imagine that you have collided carts on an air-track to investigate conservation of momentum. Your results show that momentum after a collision is usually a little less than the momentum before. Which statement best explains your observation?

Momentum changed slightly due to friction.

Thermal energy is transferred to a substance in its gaseous state inside an open container. Which result is most likely?

The particles will move more quickly.

How do physicists hope to use particle accelerators to explain the origins of the universe?

by colliding atomic nuclei to approximate what happened shortly after the Big Bang

An object traveling along a circular path is undergoing __________________ directed toward the center of the path.

centripetal acceleration

Three objects collide with each other simultaneously at a point. Before the collision, Object A, which had a mass of 2.0 kg, had an acceleration of 1.0 m/s2 southeast. Object B, which had a mass of 4.0 kg, had an acceleration of 2.0 m/s2 northwest. Object C, which had a mass of 6.0 kg, had an acceleration of 1.0 m/s2 northeast. After the collision, the three objects stick together. What is the acceleration of the combined mass?

0.71 m/s2 north

A 110 g hockey puck slides across the frictionless surface of an ice rink at 2.2 m/s. It collides with a 420 g water bottle at rest on the ice. The water bottle slides off at 0.84 m/s in the direction of the puck's original velocity. What is the puck's final velocity?

1.0 m/s opposite its original motion

A lab cart is moving on a level track. Using a motion sensor, a computer creates the velocity--time graph shown below. What is the displacement of the lab cart from 3.0 to 3.5 s?

1.1 m

A scientist starts with two identical circuits. In the first, she doubles the current and doubles the voltage. In the second, she halves the current and doubles the voltage. What is the ratio of the resistance in the first circuit to the resistance in the second circuit?

1/4

A stone is placed 35.0 cm in front of a lens. The lens has a focal length of 10.0 cm. Where will the image of the stone appear?

14.0 cm beyond the lens

Suppose 8.2 kg of steam at 2.4 atm pressure is trapped inside a closed container of fixed volume at a temperature of 430.0 K. A Bunsen burner applies 742,000 J of thermal energy to the steam. What is the pressure of the steam inside the container after heating? The specific heat of steam is 2,010 J/(kg·K).

2.7 atm

A certain object has 11 J of kinetic energy while traveling at 22 m/s. At what speed does it need to travel to have 15 J of kinetic energy?

26 m/s

Jenna lifts a 5-kg mass through a displacement of 2 m in 3 s. How much time does Kendra need to lift a 10-kg mass through a distance of 1 m in order to have the same power output?

3 s

The following equations are equivalent to find the force that results from moving charges in a magnetic field: \\F=qvB\sin\theta\\F=IlB\sin\theta F = q v B sin ⁡ θ F = I l B sin ⁡ θ In the second equation, I I is the electrical current, l l is the length of a piece of test wire in the magnetic field, B B is the magnetic field strength, and \theta θ is the angle between the current and the field. The equation can be rearranged to find the magnetic field around a wire carrying a current. What is the magnetic field that exerts a force of 2.4 × 10-4 N on a current of 15 C/s in a 0.5-m length of wire placed perpendicular to the magnetic field?

3.2 × 10-5 T

Two samples of 2.0 L of water are heated by adding 50.0 J of thermal energy to each. Both samples are at the same pressure, 1 atm. What are the possible initial temperatures of the two samples?

300 K and 350 K

A system does 40 joules of work in 100 seconds. If the system can supply constant power, how long would it take the same system to do 1200 joules of work?

3000 seconds

What is the maximum possible efficiency of a heat engine that takes in 345 kJ of thermal energy and expels 182 kJ of thermal energy to the environment?

47%

If a circuit has a power of 25.0 W and a current of 5.00 A, what is the voltage in the circuit?

5.00 V

A photogate is placed in a fixed position on a circular track of radius 5.0 m. A cart drives around the track with a constant speed. If the light beam of the photogate is interrupted at regular intervals of 5.0 s. The speed of the cart is

6.3 m/s

A projectile was launched from the ground at an unknown angle. The initial vertical component of the velocity was 2.0 m/s. If the projectile's displacement from the time it was launched until the time it hit the ground was 4.0 m, what was its initial horizontal velocity?

9.8 m/s

Summarize the key feature of atoms that makes atomic spectroscopy possible

Atoms absorb or emit only particular wavelengths of light.

An orange ball is dropped off a 50-m high cliff at the same time a green ball is thrown horizontally off the same cliff. Compare the time each ball takes to reach the ground below.

Both balls hit at the same time.

Diagrams 1 and 2 show the location of objects and their corresponding images when placed in front of a convex lens. In which diagram does the lens have a greater focal length?

Diagram 1

Diagrams of electric fields and magnetic fields often look similar. What is an important difference between electric field lines and magnetic field lines?

Electric field lines start and end on charges, while magnetic field lines form closed-loop paths to and from the poles.

Two balloons are rubbed on a sweater, giving them a net charge. They are initially at a small distance d apart from one another and experience a force F. If they are then moved to a distance of 2d apart from one another, what is the magnitude of the force then?

F/4

A student is using the equation for the force on a charge in an electric field. The charge value is negative. He writes an answer that indicates the force is in the same direction as the field. What is the student's mistake?

He should have written that the force is in the opposite direction from the field.

A solid tablet made of multiple substances is dropped into an acidic solution. One of the molecules in the substance reacts with the acidic solution. Which of the following characteristics of this tablet would affect the rate of the chemical reaction? I. The ratio of surface area to volume of the tablet II. The concentration of the reactant molecule in the tablet III. The ratio of mass to volume of the tablet

I. The ratio of surface area to volume of the tablet II. The concentration of the reactant molecule in the tablet

A liquid and a solid substance are mixed together. The solution begins to bubble and produce CO2 gas. The production of the gas is measured by a solution of bromothymol blue, which indicates that the reaction takes about 2 minutes. The reaction is performed a second time, but a catalyst, A, is added. The reaction takes 45 seconds. The reaction is performed a third time with catalyst B added. It now takes about 4 minutes. Which of the following is the most appropriate conclusion to draw from these observations?

In this particular reaction, catalyst A is a positive catalyst while catalyst B is a negative catalyst.

As atomic number increases across a row of the periodic table from left to right, why do atomic radii decrease?

Increasing positive charge from the protons holds all the negatively charged electrons more closely.

A researcher sends a particle into a region with a strong electric field directed perpendicular to the particle's velocity. The diagram illustrates the particle's trajectory. Which hypothesis must be true of the particle?

It is electrically neutral.

An object of mass 2 kg travels through outer space in a straight line at a constant speed of 100 m/s. One may most correctly conclude that

It is subject to a net force of zero.

Why is the standard model unable to predict a particle's mass?

It lacks a mathematical model to predict mass.

A certain chemical reaction takes roughly 1 minute to complete. If the reaction was run again, but the temperature and pressure of the reactants was lower, what would likely happen to the reaction rate?

It would decrease.

Theoretical physicists sometimes hypothesize an undiscovered particle called a "graviton". The graviton would be responsible for the gravitational force. Assess whether you expect the graviton to be part of the standard model.

No, because the standard model describes only the fundamental forces other than gravity.

Which of the following is an accurate example of Newton's third law?

None of the answers below: A. A hockey puck slides at constant velocity on frictionless ice. B. A girl is able to pull a sled by exerting greater force on the sled than the sled exerts on her; this produces a net force on the sled. C. A punter kicks a football high into the air; the force on the person's foot is less than the force on the football.

The magnitude of the electric force between two objects can be determined using

None of the listed answers are correct. Coulombs Law.

Which of the following is the correct formula for calculating power?

P = W/t

An adult is pushing a child on a swing. How can she push the swing so that it swings out to large amplitudes?

She should apply a force to the swing so that it moves at its resonant frequency.

Which of the following is a difference between electromagnetic waves and sound waves?

Sound waves are longitudinal, while electromagnetic waves are transverse.

An object of mass m is placed on Spring A, which is compressed by distance x. The spring is released and the velocity of the pushed object as it leaves the spring is measured. The experiment is repeated with the same object on Spring B, which is compressed by the same distance x.The object travels faster when pushed by Spring B. What can be concluded?

Spring A's spring constant is lower than Spring B's.

Two cars collide in a collision. Which of the following best explains whether or not the atoms in the cars actually make contact?

The atoms do not make physical contact. Instead, there is a repulsive electric force that acts at a distance.

A student is using a computer to study the effect of combining the electric fields of groups of charged particles in different ways. Which of the following is a feature of all the diagrams produced by the computer?

The electric field at each location is the vector sum of the fields from the individual particles.

Which of the following is the best critique of the statement "The gravitational force between atomic masses is the primary force that drives chemical reactions"?

The electric force is the primary force that drives chemical reactions. The gravitational force is very weak in comparison.

Whenever energy changes form, people sometimes say that some energy is "lost." What is meant by this?

The energy is not truly lost; it transforms into forms that are not easily put to use.

Glow sticks emit colorful light when they are first bent. The bending motion breaks a capsule inside the glow stick, which allows two chemicals to mix and react. What is the source of the light?

The energy of the light comes from the energy stored in chemical bonds.

If a force is applied to an object, which of the following must be true?

The force applied will contribute to the total net force.

A girl pulls a sled with a force of 40 N. The weight of her sled is 80 N. A boy pulls a different sled with a force of 30 N. The weight of his sled is 70 N. Which sled exerts the force of greater magnitude on the child dragging it?

The girl's sled exerts the force of greater magnitude.

What is true of a moving object compared to an object at rest?

The moving object has kinetic energy and momentum, the object at rest has neither.

A student analyzed the motion of an object in two different ways. In one, she summed up the distances traveled by the object. In the other, she added the displacement vectors. The distance sum was a large positive number, while the sum of the vectors was one short displacement vector with a small positive magnitude. Which of the following statements is most likely true?

The object's final location was near its initial location.

You are given a sample of matter in a container, and your instruments show that its temperature is close to standard room temperature. Explain why this is most likely not a plasma.

The temperature of plasma is usually much higher than room temperature.

If two equal but opposite waves (one is at a maximum while the other is at a minimum) interfere with each other, what will happen?

The waves will completely cancel each other out.

One end of an iron bar is heated. What is the effect, if any, on the particles at the other end of the bar?

Thermal energy will eventually be transferred to them through the bar as the kinetic energy of the bar's particles distributes throughout the bar.

A mass oscillates on a spring with simple harmonic motion. How does the magnitude of the force of the spring compare with the magnitude of the displacement of the mass?

They are proportional to each other.

Observe the following waves. How are the waves different?

They have different polarizations.

In chemical reactions, valence electrons are sometimes transferred to other atoms. Assess the following explanations of why this occurs and select the best one.

Valence electrons are more loosely held by the nucleus of their own atom and are free to be attracted to other atoms.

Assess the following statement to determine its accuracy and clarity: "Valence electrons have no attraction to their own atom and therefore move to other atoms in a chemical reaction." Which of the following modifications, if any, is best?

Valence electrons are weakly attracted to the nucleus of their own atom. During a reaction, they are attracted to the nucleus of another atom and form a bond.

If W is work, F is the magnitude of the force, d is the distance, and a is the relevant angle, the formula for calculating the work done by the force is

W = Fd cos(a)

Three walls filled with different materials are being tested for their thermal conductivity. Each is exposed to the same indoor and outdoor temperatures and have the same area. Wall A is twice as thick as Wall B, and Wall B is twice as thick as Wall C. The rate of heat transfer for the three walls is as follows: Wall A: 15 kW, Wall B: 25 kW, and Wall C: 54 kW. Which wall has the best thermal conductivity for insulating purposes?

Wall B

Which of the following most closely models a sound wave?

a spring stretched out left to right while being shaken left to right

What happens at absolute zero?

atoms and molecules stop moving

By measuring the potential energy of an object relative to the ground, and the object's mass, you can calculate its speed when it hits the ground. Explain why you can do this.

because gravitational potential energy can convert to kinetic energy

A horse pulls on a carriage. By Newton's third law, the carriage pulls back on the horse with equal force. Why do the action and reaction forces just described not balance each other out?

because the action force acts on the carriage, while the reaction force acts on the horse

The reaction below is an example of what type of process? 14/6C -->14/7N+ e- +v

beta decay

Choose the best way to complete the following statement: Given that it takes years for steel to turn into rust, this process

can be a chemical reaction since some chemical reactions take place very slowly

Which is not required for work to take place?

constant speed

A technician is repairing a break in an electrical circuit. Which material would be the best choice to pass current from one part of the circuit to another?

copper

Four identically shaped bars made of different materials are submerged in a pot of boiling water. After a short time, which bar would most likely be hottest?

copper

In a physics motion study, students established a frame of reference for measurements. Which of the following is their most likely choice?

distances from two walls and the floor

If you double the mass of an object while keeping the acceleration constant, you will

double the force on the object

A mass hangs on a vertical spring at equilibrium. It is then compressed upward and released. In which direction does the restoring force act?

downward

An electric force would exist between which of the following subatomic particles?

electron and proton

By which physical principle do systems tend to develop from order and concentrated energy toward disorder and distributed energy?

entropy

A nuclear power plant harnesses nuclear energy by splitting apart the nuclei of atoms. This process is known as _____.

fission

Two or more vectors added together

give a resultant vector

How could a small, lightweight pencil and a large, heavier hammer provide the same impulse?

if the force imparted by the pencil was allowed to act for much longer than the force from the hammer

Suppose you are wiring an emergency shutdown switch for a factory. How should the switch be wired?

in series

In a given frame of reference, objects in motion tend to stay in motion at constant speed, in straight lines, unless acted on by outside forces. This kind of reference frame is

inertial

The formula for sulfuric acid is H2SO4. The bonds in sulfuric acid are covalent. In which region of the Venn diagram does it belong?

intersection of molecules and compounds

In physics, how is a two-dimensional vector often resolved for analysis?

into perpendicular x and y components

The number of relatively orderly microstates in a complex system

is small compared with the number of relatively disorderly ones

A student hangs a wood block from a spring. The student pulls the block downwards so the spring is stretched and holds the block at rest. What type of energy does the wood not have?

kinetic energy

For an ideal monotonic gas, which of the following types of energy is primarily responsible for its overall internal energy?

kinetic energy

Inside a perfectly insulated, closed container, gas molecules change among different equivalent microstates. This system is characterized by

no net change in entropy

Which of the following characteristics is common to all frames of reference?

one or more coordinate axes

When all the acceleration acting on an object is centripetal, what changes?

only its direction

Does an object with constant speed also have constant velocity?

only when the direction is also constant

Two atoms are bonded together. Which of the following actions would decrease the strength of this bond by the greatest amount?

pulling the atoms farther apart

Exothermic reactions ____________, while endothermic reactions ___________.

release thermal energy; absorb thermal energy

What quantity could you measure to differentiate a superconductor from a standard conductor?

resistance

In uniform circular motion, how are the directions of the centripetal force and centripetal acceleration oriented?

same direction, toward the center

It can be said that the force of tension in a rope relies on the electric force because ___________.

the electric force holds atoms in the rope together

Two gases are in a sealed box, separated by a panel. The panel is removed without disturbing the gases. Some time later,

the gases have thoroughly mixed and the degree of order has decreased

Which of the following processes represents an isochoric process?

the gases inside an aerosol can increase in pressure due to the addition of thermal energy

One interesting feature of electric motors is that their normal sequence of cause-effect events can often be reversed. Beginning with the movement as the input, what is their useful output under these conditions?

the generation of electric current in their wires

A spring is stretched from rest and released. Which of the following describes the frequency of the spring?

the number of times the spring moves up and down in 1 second

What is commonly used to identify the type of a sample of atoms?

the pattern of light emitted or absorbed

This graph reflects the thermal energy of a substance when heat is applied at a constant rate. According to the graph, during which phase of the heating curve do particles move the most quickly?

vapor

What happens to your weight if you are standing on the surface of Jupiter, where the force of gravity is approximately 2.5 that of Earth?

weight increases by a factor of 2.5