Physical Science Test 2
The volt is a measure of the difference in electrical potential energy between two points. Select one: True False
True
Calculate the period of a wave vibrating at the rate of 4 cycles per second
0.25 seconds
Convert 2.5 Cal to cal
2500 cal
Convert 10.8 cal to Joules.
45.2 J
A sound of 20-dB intensity is twice in loudness as one of 10-dB. Select one: True False
False
An object becomes positively charged by gaining protons. Select one: True False
False
Convection current is associated with radiation Select one: True False
False
During resonance, the amplitude of the resulting wave becomes larger than the natural wave from which it was resonated. Select one: True False
False
Heat transferred by moving air molecules is called radiation. Select one: True False
False
If we supply a conductor with some charge, the gained charge collects in one place as a static electricity. Select one: True False
False
In solids cooler atoms hit hotter atoms to transfer heat. Select one: True False
False
Neutrons are in the nucleus and have a negative charge Select one: True False
False
Protons and electrons repel because they are unlike charges. Select one: True False
False
The electric field moves from the power plant to homes in a direct current. Select one: True False
False
The north end of a suspended magnet will point to the magnetic north pole (i.e. geographic south pole). Select one: True False
False
The number for the Celsius scale is larger than the number for the Fahrenheit scale for the same temperature. Select one: True False
False
The sum of all the energy of the molecules of an object is called the temperature of that object. Select one: True False
False
We can transfer protons to develop a positive charge. Select one: True False
False
When you are moving toward a stationary source of a sound, the sound frequency will appear lower than it actually is. Select one: True False
False
Whether the sonic boom occurs or not does not depend on how fast the object travels Select one: True False
False
The smaller the conductivity value slower is the conduction of heat Select one: True False
True
As the voltage increases, the current in the wire increases. Select one: True False
True
Conduction occurs by the vibration of contacting molecules Select one: True False
True
Electron number transferred (gained or lost) is responsible for the charge in an atom. Select one: True False
True
Even at freezing cold outside, the molecules in objects are vibrating. Select one: True False
True
Heat flow in boiling liquid occurs by the actual movement of molecules. Select one: True False
True
If a conducting wire is passed with a current, it produces a magnetic field around itself. Select one: True False
True
It is possible to stop completely the vibration of molecules at absolute zero, 0 K. Select one: True False
True
Protons and neutrons are in the nucleus of an atom. Select one: True False
True
Sound energy can be converted to electrical energy as well as electrical energy can be converted back to sound energy using a single device. Select one: True False
True
Sound travels much faster through pure hydrogen than through air (a mixture of nitrogen and oxygen). Select one: True False
True
Sound wave is a longitudinal wave. Select one: True False
True
The amplitude of a wave is the height of a crest or a depth of a trough Select one: True False
True
The molecules of a gas are much farther apart than molecules in a solid or liquid. Select one: True False
True
The nutritionist's Calorie is really a kilocalorie. Select one: True False
True
1.5 × 103 C charge is developed in 2.5 minutes throughout a conductor. Calculate the current flowing through that conductor. Select one: a. 10 A b. 600 A c. 3750 A d. 150 A e. 2.25 x 105 A
a. 10 A
Calculate the potential if 600 J work is done by a charge of 60 C. Select one: a. 10 V b. 10 J c. 36000 J.C d. 0.1 V e. 36000 V
a. 10 V
Find the depth of the ocean if the sound from a ship reaches the bottom in 8.0 seconds. Use the speed of sound in water to be 1497 m/s Select one: a. 12,000 m b. 1497 m c. 24,000 m d. 8 km e. 6000 m
a. 12,000 m
What is the range of normal human hearing? Select one: a. 20 Hz to 20, 000 Hz b. 20 Hz to 2,000 Hz c. 20 Hz to 120, 000 Hz d. 50 Hz to 20, 000 Hz e. 0 - 120 Hz
a. 20 Hz to 20, 000 Hz
Convert 75oF to oC Select one: a. 23.9 oC b. -198 oC c. 9,7 oC d. 348 oC e. 103 oC
a. 23.9 oC
Convert 312K to oC Select one: a. 39oC b. 312oC c. 585oC d. 155.6oC e. 0oC
a. 39oC
Two tanks have 500 L water each at two different temperatures. The first one at 70oC and the second one at 40oC. Which is true regarding the total amount of heat? Select one: a. 70oC has more heat since the vibration rate is high for the same given quantity b. 40oC has more heat because lower the temperature, higher the heat c. 70oC has more heat since the number of molecules is high there d. 40oC has more heat since the number of molecules is high there e. cannot be compared because of the same amount of matter
a. 70oC has more heat since the vibration rate is high for the same given quantity
Two beakers contain 300 mL and 100 mL water, respectively, both at 80oC. Which is true regarding the vibration of molecules? Select one: a. Both have same vibration because they are at the same temperature b. 300 ml has more vibration because it has many molecules c. 100 ml has more vibration since it has less number of molecules d. vibration rate does not depend on temperature e. cannot be determined based on the given information
a. Both have same vibration because they are at the same temperature
Sound waves in air Select one: a. all of the given choices are correct. b. vibrate the molecules as the wave moves forward. c. undergo refraction when they pass through warm and cold air. d. are produced by something vibrating. e. are longitudinal waves.
a. all of the given choices are correct.
The characteristic of a sound wave that you interpret as loudness is the most closely related to Select one: a. amplitude b. frequency c. wavelength d. speed e. cycle
a. amplitude
What is the best difference between condensation and rarefaction? Select one: a. condensation is the region in the medium where the molecules are close together and rarefaction is the area in which the molecules are further apart. b. rarefaction is the region in the medium where the molecules are close together and condensation is the area in which the molecules are further apart. c. condensation is the region in the medium where the molecules are close together and rarefaction is the area in which the molecules are mixed with other types of molecules d. condensation increases the speed of sound while rarefaction decreases the speed of sound. e. condensation helps to flow the sound rarefaction does not.
a. condensation is the region in the medium where the molecules are close together and rarefaction is the area in which the molecules are further apart.
There are two totally identical waves, one is coming from the east and the other is coming from the west. What happens when the trough of one wave meets the trough of the other wave? Select one: a. constructive interference b. destructive interference c. resonance d. reflection e. refraction
a. constructive interference
You are able to hear sounds from farther away on a cool night because sound waves are refracted toward Select one: a. cooler air near to the ground. b. cooler air far above the ground c. warmer air near to the ground d. warmer air far above the ground
a. cooler air near to the ground.
The unit of electric charge is called a(an) Select one: a. coulomb b. ampere c. ohm d. volts e. watts
a. coulomb
What is it that travels through an electric circuit at near the speed of light? Select one: a. electric field b. magnetic lines c. electrons d. ions e. protons
a. electric field
A statement that the energy supplied to a system in the form of heat, minus the work done by the system, is equal to the change in internal energy represents the Select one: a. first law of thermodynamics. b. 2nd law of thermodynamics. c. 3rd law of thermodynamics. d. law of internal energy e. law of temperature change
a. first law of thermodynamics.
The higher the frequency of a sound wave Select one: a. higher the pitch b. longer the wavelength c. lower the intensity d. higher the amplitude e. higher the speed
a. higher the pitch
Bending of sound while going from low temperature to high temperature is called Select one: a. refraction b. interference c. reflection d. resonance e. noise
a. refraction
The amount of heat gained to increase the temperature of 1 gram of a substance by 1 degree Celsius is known as Select one: a. specific heat b. latent heat c. heat gained d. temperature change
a. specific heat
When we change the direction of current in the coil surrounding a magnet, the magnetic pole also changes. Why? Select one: a. this is a temporary magnet whose poles depend on the current direction that created it b. this is a temporary current whose direction depends on the magnet which created it c. this is an induction of a permanent magnet from the current d. the current and magnet energy are interchangeable e. none of the reason supplied clearly explains the magnetic induction
a. this is a temporary magnet whose poles depend on the current direction that created it
What does a transformer actually increase or decrease? Select one: a. voltage b. current c. power d. resistance e. energy
a. voltage
What is the cause of the Doppler effect? Select one: a. wave-front size being changed due to the position change of the source or the listener b. frequency being changed due to change in type of source c. intensity being changed due to change in nature of source d. nature of sound being changed due to change in position of listener or the source e. thunderstorm
a. wave-front size being changed due to the position change of the source or the listener
According to Ohm's Law, what is the potential if 12 amps current flows in a resistor of 2 ohms? Select one: a. 6 V b. 24 V c. 1/6 V d. 0 V e. 10 V
b. 24 V
Consider an electrical transformer that has 20 loops on its primary coil and 40 loops on its secondary coil. What is the voltage in the secondary coil if the primary coil is supplied with 120 V? Select one: a. 120 V b. 240 V c. 60 V d. cannot be calculated using the given information e. 480 V
b. 240 V
Which thermodynamic law says that you cannot convert 100 percent of a heat source into mechanical energy? Select one: a. 1st law of thermodynamics b. 2nd law of thermodynamics c. 3rd law of thermodynamics d. law of increasing entropy
b. 2nd law of thermodynamics
Two beakers contain 300 mL and 100 mL water, respectively, both at 80oC. Which of the following is true regarding the heat energy? Select one: a. 300 ml has more heat because molecules are vibrating faster b. 300 ml has more heat because it has many molecules c. 100 ml has more heat because molecules are vibrating faster d. both have same heat because they are at the same temperature. e. cannot be compared from the given information
b. 300 ml has more heat because it has many molecules
Calculate the specific heat capacity of a 5-kg metal ball which gains 500 J of heat to increase its temperature from 10oC to 30oC Select one: a. 5 J\kg b. 5 J/kgoC c. 2000 J/kgoC d. 0.2 J/kgoC e. 50, 000 J
b. 5 J/kgoC
How much electric current is produced if 120 Coulombs of charge flows in 20 seconds? Select one: a. 100 amp b. 6 amp c. 2400 amp d. 60 amp e. 144000 amp
b. 6 amp
What happens during a sonic boom in a supersonic jet? Select one: a. an object travels faster than the sound b. An airplane exceeds the speed of sound and clouds get clustered near the tail c. clouds get around the object when flying d. an explosion occurs due to the airplane travelling faster than sound e. sonic rays travel faster than the speed of sound
b. An airplane exceeds the speed of sound and clouds get clustered near the tail
What is not consistent with the Second Law of Thermodynamics? Select one: a. In heat engines, not 100% of the heat from the hot reservoir is converted to work. b. Heat flows from cold to hot regions spontaneously. c. Natural processes are always in disorder. d. Real processes are irreversible processes. e. All of the given choices are consistent
b. Heat flows from cold to hot regions spontaneously.
If T = 1/f, then how are T and f related? Select one: a. T is directly proportional to f b. T is inversely proportional to f c. T is a factor of f d. T and f are unrelated e. cannot be said just from the formula
b. T is inversely proportional to f
Convection is a process that transfers heat by Select one: a. molecule to molecule contact. b. actual movement of molecules. c. vibration of molecules. d. without needing any molecule.
b. actual movement of molecules.
Which of the following best describes amplitude and cycle? Select one: a. amplitude tells about how big a wave is and frequency tells how intense a wave is. b. amplitude tells about how big a wave is but frequency tells how many waves are made in one second c. amplitude gives the how many waves are made and cycle tells the intensity of a wave d. amplitude gives the energy of a wave and frequency gives the strength of a wave e. amplitude and frequency basically are the same quantities
b. amplitude tells about how big a wave is but frequency tells how many waves are made in one second
There are two totally identical waves, one is coming from the east and the other is coming from the west. What happens when the crest of one wave meets the trough of the other wave? Select one: a. constructive interference b. destructive interference c. resonance d. reflection e. refraction
b. destructive interference
The number of complete waves made in 1 second time is called the wave's Select one: a. period b. frequency c. cycle d. wavelength e. amplitude
b. frequency
Earth has magnetism because Select one: a. it gained its magnetism from the sun. b. it has moving molten core of nickel and iron c. it has a giant magnet inside its surface d. there are north and south poles
b. it has moving molten core of nickel and iron
If you want to increase the voltage using a transformer, which of the following option would you want to use and for what reason? Select one: a. more in the primary and fewer in the secondary, voltage is directly related to the number of coils b. more in the secondary and fewer in the primary, voltage is directly related to the number of coils c. more in the primary and fewer in the secondary, voltage is inversely related to the number of coils d. more in the secondary and fewer in the primary, voltage is inversely related to the number of coils e. numbers should be given to decide on this question
b. more in the secondary and fewer in the primary, voltage is directly related to the number of coils
An atom that has gained one or more electrons will become a Select one: a. positive ion b. negative ion c. positron d. de-ionized atom e. neutron
b. negative ion
Ultrasonic images are obtained from the inside organs of our body. This process is called Select one: a. refraction b. reflection c. interference d. resonance e. noise
b. reflection
Which of the following is a perfect match? Select one: a. resistance increases - when the length of the wire decreases. b. resistance decreases - when the cross-sectional area of the wire increases. c. resistance decreases - when the temperature of the wire increases. d. resistance increases - when the wire is made of good conductor material.
b. resistance decreases - when the cross-sectional area of the wire increases.
In the equation: Q = mc∆t, the c stands for the Select one: a. heat gained b. specific heat c. latent heat d. number of calories gained or lost e. temperature change
b. specific heat
Speed of sound in water is 1497 m/s, while in steel it is 5940 m/s. Why this difference? Select one: a. water molecules stick to each other but steel molecules do not b. steel molecules are close enough to transfer the sound effectively and fast compared to water c. steel is a mechanical medium but water is not d. water has a high sound absorbing capacity than steel
b. steel molecules are close enough to transfer the sound effectively and fast compared to water
The process by which solids vaporize without first becoming a liquid is called Select one: a. condensation b. sublimation c. evaporation d. boiling e. freezing
b. sublimation
A sound that is perceived as twice as loud requires Select one: a. twice the intensity. b. ten times the intensity c. a hundred times the intensity d. four times the intensity e. reduced intensity by 1/10
b. ten times the intensity
When a switch is closed (connected) in a DC electrical circuit, Select one: a. electrons flow through the conductor at a very slow speed. b. the electric field moves through the conductor at the speed of light. c. more current flows as the potential difference is decreased. d. nothing flows through the wire since this is a direct current circuit e. protons flow through the wire at a speed of light
b. the electric field moves through the conductor at the speed of light.
When a magnet is cut into two halves Select one: a. the two poles are separated b. the two pieces become new magnets c. the magnetic field is divided into half d. the magnetism is lost e. the magnetic energy is divided
b. the two pieces become new magnets
An electric current is a(an) Select one: a. total volt per unit time (V/t). b. total charge per unit time (q/t). c. electrical equivalent of gravitational potential difference (Vg). d. total joules per coulomb of charge (J/Q).
b. total charge per unit time (q/t).
Longitudinal waves with a frequency above 20,000 Hz are Select one: a. impossible b. ultrasonic c. infrasonic d. audible e. electromagnetic
b. ultrasonic
In longitudinal waves, the medium Select one: a. vibrates perpendicular to the motion of the wave. b. vibrates in the same direction of the motion of the wave. c. moves in a circular motion. d. doesn't vibrate; the disturbance just moves through the medium. e. doesn't have any effect on the wave
b. vibrates in the same direction of the motion of the wave.
Which of the following processes has increased entropy? Select one: a. gases turning into liquids b. wax melting to liquid c. water freezing to ice d. pieces of puzzle put together
b. wax melting to liquid
Consider an electrical transformer that has 20 loops on its primary coil and 40 loops on its secondary coil. What is the primary loop current if the secondary coil has 2 amp? Select one: a. 2 amp b. 4 amp c. 1 amp d. 0.5 amp e. 20 amp
c. 1 amp
Calculate the power of an electric heater, which runs with a voltage of 12 V and produces 2.5 A current. Select one: a. 1500 W b. 1500 KW c. 30 Watts d. 30 kilowatts e. 4.8 W
c. 30 Watts
Convert 100oF to Kelvin (Remember, this is a two-step calculation. First convert to oC) Select one: a. 37.8 K b. 68 K c. 311 K d. -235.4 K e. 273.15 K
c. 311 K
Which statement of the following is true? Select one: a. 500 mL water at 25oC has more vibration of molecules than 250 mL water at the same temperature. b. 250 mL water at 45oC has more vibration of molecules than 250 mL water at the same temperature. c. 500 mL water at 45oC has more heat energy than 250 mL water at the same temperature. d. A 250 mL water at 25oC has more heat energy than 500 mL water at the same temperature. e. None of the given choices is true.
c. 500 mL water at 45oC has more heat energy than 250 mL water at the same temperature.
Which is true about solid molecules? Select one: a. They are able to flow b. They can transfer heat by actually moving c. They are tightly packed and can vibrate d. They cannot transfer any heat e. They transfer heat by convection
c. They are tightly packed and can vibrate
Which of the following statement is false? Select one: a. When frequency increases, the period decreases. b. Nodes are the destructive interference points. c. While we speak, the air molecules are vibrating up and down in every direction. d. Sound interferences are sometimes useful.
c. While we speak, the air molecules are vibrating up and down in every direction.
A magnetic field is produced around a conductor when- Select one: a. a large amount of electric charge collects at a point on that conductor. b. there is shortage of stationary electric charges on that conductor. c. charges move through that conductor. d. opposite charges attract and cancel each other somewhere along that conductor.
c. charges move through that conductor.
Which statement best describes the electron theory of charge? Select one: a. atoms are the basis of matter b. electrons attract protons to cause electricity c. electric current can be considered as moving charge due to electron flow d. protons flow in a conductor to cause electricity e. when we rub substances we produce electricity
c. electric current can be considered as moving charge due to electron flow
Resonance occurs when- Select one: a. constructive interference occurs between natural and external source of vibration b. intensity matches between natural source and external source of vibration c. frequency matches between natural and external sources of vibration d. destructive interference occurs between natural and external vibration
c. frequency matches between natural and external sources of vibration
Musical beats of three different sounds are mixed to get a clear sound. This process is called Select one: a. refraction b. reflection c. interference d. resonance e. noise
c. interference
A noise level of 65 decibels is measured for Select one: a. whisper b. jet plane c. normal conversation d. library conversation e. shout
c. normal conversation
What is the reason that the liquid can flow? Select one: a. the molecules are tightly packed b. the molecules are free to move, detached from each other c. the molecules are loosely packed and can slide past each other d. the molecules can convert into gas easily
c. the molecules are loosely packed and can slide past each other
The source comes closer to the listener
frequency increases
Under which condition will the induced voltage in a coil of wire decrease? Select one: a. the magnet inside the coil is moved in and out faster than slower b. the magnet used inside the coil is a stronger magnet than a weak magnet c. the number of turns in the coil is fewer d. the conductor in the coil is made of copper instead of iron e. it will not decrease under any of the given conditions
c. the number of turns in the coil is fewer
What are two properties of mechanical waves? Select one: a. they need medium to travel, they travel fast in gases b. they can travel in vacuum, they travel at the speed of light c. the wave propagates but the medium remains in place, they need medium to travel d. mechanical waves are faster than light waves, electrons are the medium of travel e. the medium propagates but the wave remains in place, they need medium to travel
c. the wave propagates but the medium remains in place, they need medium to travel
Electric field lines are drawn Select one: a. to show where the positive charge is. b. to show where the negative charge is. c. to show the direction of the electric field. d. radiating outward like spokes on a wheel. e. to show the magnetic field around the charge
c. to show the direction of the electric field.
When does echo occur? Select one: a. when we speak in front of a sound absorbing surface b. when we shout in front of a tall mountain c. when the gap between the sound production and the reflection is 0.1 second d. when the reflecting surface is smooth and sharp e. when there is no noise around
c. when the gap between the sound production and the reflection is 0.1 second
Which is not true about gas molecules? Select one: a. Since they are far apart, they come in contact only when they collide. b. They can transfer heat by actually moving c. They are loosely packed and are always moving d. Since they are far apart, they cannot transfer heat
d. Since they are far apart, they cannot transfer heat
In an electric motor Select one: a. electrical energy is converted to mechanical energy. b. stationary field magnet and movable electromagnet work together. c. strength of field magnet influences the movement of electromagnet. d. all the given choices are correct e. none of the given options are correct
d. all the given choices are correct
Mechanical waves can pass through Select one: a. solid b. liquid c. gas d. all the given choices are correct e. ice
d. all the given choices are correct
Molecules in a solid Select one: a. are harder than molecules in liquids or gases. b. transfer heat to their neighbors by a process called convection. c. have no internal energy because they are not moving around. d. are held in nearly fixed positions by strong attractive forces.
d. are held in nearly fixed positions by strong attractive forces.
What is not true about the electric current? Select one: a. that the current is a result of flow of electrons b. if there is no potential difference, no current will flow c. higher the potential, higher will be the current flow d. current flows from low potential to high potential
d. current flows from low potential to high potential
Through which medium will sound travel most rapidly? Select one: a. water b. air c. steel d. diamond e. gold
d. diamond
Water vapor can change to liquid only when Select one: a. it absorbs energy from the surroundings. b. its molecules go far from each other causing expansion. c. its temperature rises slightly. d. it releases heat to the surroundings.
d. it releases heat to the surroundings.
One musical instrument is tuned with another musical instrument. The process is called Select one: a. refraction b. reflection c. interference d. resonance e. noise
d. resonance
According to Ohm's law Select one: a. voltage and current are independent of each other b. that less current flows when a higher voltage is applied. c. that for constant voltage, a greater resistance means more current will flow. d. that the current in a circuit increases if the potential difference increases.
d. that the current in a circuit increases if the potential difference increases.
Molten metal solidifies into a metal block
decrease in entropy
papers bound to make a book
decrease in entropy
Two tanks have 500 L water each at two different temperatures. The first one at 70oC and the second one at 40oC. Which one has a higher amount of vibration of molecules? Select one: a. cannot be said based on the temperature b. 40oC one has higher rate of vibration since it has high heat c. 40oC has higher rate of vibration since it has more freedom d. 70oC has higher rate of vibration since it has more number of molecules e. 70oC has higher rate of vibration since it is at a higher temperature.
e. 70oC has higher rate of vibration since it is at a higher temperature.
When a water bottle is taken out of a fridge, the outside wall collects water droplets. this is the example of- Select one: a. sublimation b. boiling c. evaporation d. freezing e. condensation
e. condensation
Which one of the following does not represent static electricity? Select one: a. energy in an electric car battery b. clouds during a thunderstorm c. hair and plastic comb during combing hair d. woolen clothes against our body e. energy in headphone wires from a cellular phone
e. energy in headphone wires from a cellular phone
The unit of the electric potential difference between two points is Select one: a. ohm b. watts c. ampere d. joule e. volts
e. volts
The particle in an atom which has negative charge is called
electron
The listener goes away from the source
frequency decreases
The source goes away from the listener
frequency decreases
The listener comes closer to the source
frequency increases
Frozen meat thaws under normal temperature
increase in entropy
Milk in a glass spilled out
increase in entropy
Name the method of transfer of heat that does not need a medium.
radiation