Physics Midterm
Exert 1 N for a distance of 1 m in 1 s and you deliver a power of
1 W
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
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
10.3 meters
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 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
What is the molecular mass of a water molecule?
18 amu
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?
180 m
A flywheel's mass is twice that of another of the same size and shape. The more massive flywheel's rotational inertia is
2 times the other's
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
20 cm
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
3000 N
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 bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy of
40 J
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 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
5 g/cc
At one instant an object in free fall is moving upward at 50 meters per second. One second later its speed is about
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
If a gram of antimatter meets a kilogram of matter, the amount of mass to survive is
999 grams
A force is a vector quantity because it has both
A force is a vector quantity because it has both
The impulse-momentum relationship is a direct result of
Newton's 2nd law
The conservation of momentum is most closely related to
Newton's 3rd law
An atomic mass unit (amu) is 1/12 the mass of
a carbon atom
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
about 30 m/s
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?
about 50 m/s
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
An object maintains its state of motion because it has
all of these
The force on an apple hitting the ground depends upon
all of these
Which has zero acceleration? An object
all of these
Nuclei of atoms that make up a newborn baby were made in
ancient stars
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
If a pair of helium nuclei are fused together, the result is
beryllium
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
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
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 floating ice cube contains small pieces of iron. During melting the water level will
fall
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
A car that travels twice as fast as another when braking to a stop will skid
four times as far
The scientific method is most effective in
gaining, organizing, and applying new knowledge.
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 mass of the bullet equals the mass of the gun
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
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
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
is the same for each bullet
An elephant eats less for its size than smaller animals because
its radiating area is small compared to its volume
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 actually
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 and may be 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 4 N
An object that has kinetic energy must be
moving
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
nevertheless there is still an unbalanced force on the wagon.
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 of these
As a balloon rises higher and higher into the atmosphere, its
none of these
If each dimension of a steel bridge is scaled up ten times, its strength will be multiplied by about
one hundred, but its weight by one thousand.
Most of the matter in the universe is in the
plasma state
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.
Brownian motion has to do with the
random motions of atoms and molecules.
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 for a long way
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
remains unchanged
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
If we doubled the magnifying power of the most powerful optical microscope in the world, we would
still not be able to see an atom
The pressure at the bottom of a jug filled with water does NOT depend on
surface area of the water
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
Which of the following is a scientific statement?
the moon is made of green cheese
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
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
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
the target would be safer than the shooter
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
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 completely submerged object always displaces its own
volume of fluid
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
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?
zero J
