Physics 1 Midterm

A woman lifts a box from the floor. She then moves with constant speed to the other side of the room, where she puts the box down. How much work does she do on the box while walking across the floor at constant speed?

0 J

Exert 1 N for a distance of 1 m in 1 s and you deliver a power of

1 W

A car accelerates at 2 meters per second per second. Assuming the car starts from rest, how much time does it need to accelerate to a speed of 30 m/s?

15 seconds

If each dimension of a steel bridge is scaled up ten times, its strength will be multiplied by about

by 100 and its weight by 1000

An object maintains its state of motion because it has

NOT all mass, weight, speed, acceleration

A car travels in a circle with constant speed. The net force on the car is

directed towards the center of the curve.

Which of these forces determines the chemical properties of an atom?

electrical force

The volume of matter comes mostly from its

electrons

A column that extends from sea level to the top of the atmosphere contains a certain mass of air. If the same column instead had the same mass of water in it, the height of the water column would be

NOT 3/4 meter

If a pair of helium nuclei are fused together, the result is

NOT beryllium

Which of the following is a scientific statement?

NOT none of these

A floating ice cube contains small pieces of iron. During melting the water level will

NOT remain unchanged

A horse exerts 500 N of force on a heavy wagon. The wagon pulls back on the horse with an equal force. The wagon still accelerates because

NOT unbalanced force on the wagon

Which has zero acceleration? An object

at rest, constant velocity, mechanical equilibrium

A heavy object and a light object are dropped at the same time from rest in a vacuum. The heavier object reaches the ground

at the same time as the lighter object

A bubble of air released from the bottom of a lake

becomes larger as it rises

As a helium-filled balloon rises in the air, it becomes

bigger

When an object is partly or wholly immersed in a liquid, it is buoyed up

by a force equal to the weight of liquid displaced.

Three holes are drilled in a water tower, which is filled with water, at the positions shown. Water will spurt the greatest horizontal distance from hole

c

A coin and a ring roll down an incline starting at the same time. The one to reach the bottom first will be the

coin

An elephant and a feather fall from a tree through the air to the ground below. The amount of air-resistance force is greater on the

elephant

Two equal sized buckets are filled to the top with water. One of the buckets has a piece of wood floating in it, making its total weight

equal to the weight of the other bucket

A player hits a ball with a bat. The action force is the impact of the bat against the ball. The reaction to this force is the

force of the ball against the bat

The scientific method is most effective in

gaining, organizing, and applying new knowledge.

One object has twice as much mass as another object. The first object also has twice as much

inertia

Ice cubes submerged at the bottom of a liquid mixture indicate that the mixture

is less dense than ice

The effects of scaling are beneficial to swimmers who are relatively

large

A dome-shaped house is more heat efficient than a rectangular house because a dome has

less area compared to its volume

Suppose you put very large-diameter tires on your car. Then, your speedometer will show a speed that is

lower than it is

A force is a vector quantity because it has both

magnitude and direction

A kilogram is a measure of an object's

mass

Compared to the force that brings a small car to a stop, the force required to bring a heavy truck traveling at the same speed to a stop

may be less or more

In cold weather, your hands will be warmer if you wear

mittens

A ball is thrown vertically into the air. Because of air resistance, its time coming down compared to its time going up is

more

Stand a meter stick on its end and let go and it rotates to the floor. If you attach a heavy weight to its upper end and repeat, falling time will be

more

A solid glass ball weighs 1 newton. One with twice the diameter weighs

more than 4N

An object that has kinetic energy must be

moving

A skydiver falls towards the Earth. The attraction of the Earth on the diver pulls the diver down. What is the reaction to this force?

none

As a balloon rises higher and higher into the atmosphere, its

none

Most of the matter in the universe is in the

plasma

A job is done slowly, while an identical job is done quickly. Both jobs require the same amount of work, but different amounts of

power

The weight of matter comes mostly from its

protons and neutrons

As a ball falls, the action force is the pull of the Earth's mass on the ball. The reaction force is the

pull of the ball's mass on the Earth.

An elephant eats less for its size than smaller animals because

radiating area is small compared to its volume

Brownian motion has to do with the

random motions of atoms and molecules

A boat loaded with a barrel of water floats in a swimming pool. When the water in the barrel is poured overboard, the swimming pool level will

remain unchanged

Assuming no change in temperature, as a freely-expanding helium-filled balloon rises in the atmosphere, the buoyant force that acts on it

remains nearly the same

A rifle recoils from firing a bullet. The speed of the rifle's recoil is small because the

rifle has much more mass than the bullet

The force exerted on the tires of a car to directly accelerate it along a road is exerted by the

road

Since each rolling wheel of a railroad train is tapered, the narrow part of the wheel has a tangential speed that is

smaller than that of the wide part

The force on an apple hitting the ground depends upon

speed, if it bounces, time of impact on ground

If we doubled the magnifying power of the most powerful optical microscope in the world, we would

still could not see or photograph an atom

The pressure at the bottom of a jug filled with water does NOT depend on

surface area of water

Suppose a gun were made of a strong but very light material. Suppose also that the bullet is more massive than the gun itself. For such a weapon

target would be safer than the shooter

The effects of scaling are beneficial to small creatures

that fall from great heights

Neglecting air resistance, which will roll from rest to the bottom of an incline first, an empty jar, or the same jar filled with peanut butter?

the filled jar

A 50-kg sack is lifted 2 meters in the same time as a 25-kg sack is lifted 4 meters. The power expended in raising the 50-kg sack compared to the power used to lift the 25-kg sack is

the same

A bullet is dropped into a river from a very high bridge. At the same time, another bullet is fired from a gun, straight down towards the water. Neglecting air resistance, the acceleration just before striking the water

the same

Compared to a bar of pure gold, the density of a pure gold ring is

the same

Compared to the buoyant force that acts on you when you float in fresh water, the buoyant force that acts on you when you float in the dense water of the Dead Sea is actually

the same

Compared to the atoms that make up the body of an elderly person, the atoms that make up the body of a newborn baby are

the same age

The synthesis of a large collection of information that contains well-tested and verified hypotheses about certain aspects of the world is known as a scientific

theory

The difference between impulse and impact force involves the

time the force acts on it

When an object is lifted 10 meters, it gains a certain amount of potential energy. If the same object is lifted 20 meters, its potential energy gain is

twice as much

If you push an object twice as far while applying the same force you do

twice as much work

A flywheel's mass is twice that of another of the same size and shape. The more massive flywheel's rotational inertia is

two times the others

A completely submerged object always displaces its own

volume

You wish to bolt a sign to a horizontal I-beam supporting a bridge. You will weaken the beam least if you drill the bolt-holes through the

web

Atmospheric pressure is caused by the

weight of the atmosphere

Recoil is noticeable if we throw a heavy ball while standing on roller skates. If instead we go through the motions of throwing the ball but hold onto it, our net recoil will be

zero

An apple falls from a tree and hits the ground 5 meters below. It hits the ground with a speed of about

10 m/s

A ball is thrown 125 meters upward and then falls the same distance back to Earth. Neglecting air resistance, its total time in the air is about

10 seconds

An object released from rest on another planet requires one second to fall a distance of 6 meters. What is the acceleration in meters per second per second due to gravity on this planet?

12

A car moving at 50 km/hr skids 20 m with locked brakes. How far will the car skid with locked brakes if it is traveling at 150 km/hr?

180m

What is the molecular mass of a water molecule?

18amu

A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is

30 m/s

A pot falls from a ledge and hits the ground 45 m below. The speed with which it hits the ground is about

30 m/s

A karate chop delivers a blow of 3000 N to a board that breaks. The force that acts on the hand during this event is actually

3000N

Two people, one twice as massive as the other, attempt a tug-of- war with 12 meters of rope on frictionless ice. After a brief time, they meet. The heavier person slides a distance of

4 m

A car that travels twice as fast as another when braking to a stop will skid

4 times as far

At one instant an object in free fall is moving upward at 50 meters per second. One second later its speed is about

40 m/s

A piece of rope is pulled by two people in a tug-of-war. Each pulls with 400 N of force. What is the tension in the rope?

400 N

A bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy of

40J

A ball is thrown upwards. Neglecting air resistance, what initial upward speed does the ball need to remain in the air for a total time of 10 seconds?

50 m/s

A skydiver, who weighs 500 N, reaches terminal velocity of 90 km/h. The air resistance on the diver is then

500 N

A metal block has a mass of 5 grams and a volume of 1 cubic centimeter. A piece of the same kind of metal with a volume of 2 cubic centimeters has a density of

5g/cm^3

If a gram of antimatter meets a kilogram of matter, the amount of mass to survive is

999 grams

A weightless spring is stretched 10 cm by a suspended 1-kg block. If two such springs are used to suspend the block, one spring above the other, to effectively provide one double-length spring, then the total stretch of the double-length spring will be

NOT 1cm

The conservation of momentum is most closely related to

Newton's 3rd Law

The impulse-momentum relationship is a direct result of

Newtons 2nd law

An atomic mass unit (amu) is 1/12 the mass of

a carbon atom

Compared to all liquids, solids, and gases in the universe, plasmas are the most

abundant

When you stand at rest on a pair of bathroom scales, the readings on the scales will always

add to equal your weight

Hang from a pair of gym rings and the upward support forces of the rings will always

add up to equal your weight

Nuclei of atoms that make up a newborn baby were made in

ancient stars

If the volume of an object were to double while its mass stays the same, its density would

halve

A bullet is fired from a gun. The speed of the bullet will be about the same as the speed of the recoiling gun

if the masses were equal

If a non-rotating object has no acceleration, then we can say for certain that it is

in mechanical equilibrium

If the planet Jupiter underwent gravitational collapse, its rate of rotation about its axis would

increase

If an object's mass is decreasing while a constant force is applied to the object, the acceleration

increases