physics test 1, 2, 3
A diver who weighs 500 N steps off a diving board that is 10 m above the water. The diver hits the water with kinetic energy of
5000J
A 10-N falling object encounters 10 N of air resistance. The net force on the object is
0 N
An apple weighs 1 N. The net force on the apple when it is in free fall is
1 N
The buoyant force on a one-ton blimp hovering in air is
1 ton
starting from rest, the distance a freely falling object will fall in 0.5 second is about
1.25 m
If a freely-falling object were somehow equipped with a speedometer, its speed reading would increase each second by about
10 m/s
The buoyant force acting on a 10-ton ship floating in the ocean is
10 tons.
About how high can water at sea level be theoretically lifted by a vacuum pump?
10.3 m
What is the weight of water displaced by a 100-ton floating ship?
100 tons
A gun with a muzzle velocity of 100 m/s is fired horizontally from a tower. Neglecting air resistance, how far downrange will the bullet be 1 second later?
100M
A ball is moving at 4 m/s and has a momentum of 48 kg m/s. What is the ball's mass?
12 kg.
The circumference of a bicycle wheel is 2 meters. If it rotates at 1 revolution per second then its linear speed is
2 m/s.
A floating leaf oscillates up and down two complete cycles in one second as a 10-meter long water wave passes by. What is the wave's speed?
20 m/s
A 500-N parachutist opens his chute and experiences an air resistance force of 800 N. The net force on the parachutist is
300N upward
To estimate the distance in miles of a flash of lightning, count the number of seconds between seeing the flash and hearing the accompanying thunder, then divide by
5
If you throw a stone horizontally from the top of a cliff, one second after leaving your hand its vertical distance below the top of the cliff is
5 m.
A skydiver, who weighs 500 N, reaches terminal velocity of 90 km/h. The air resistance on the diver is then
500N
The beat frequency produced when a 240-hertz tuning fork and a 246-hertz tuning fork are sounded together is
6 hertz.
A rock is thrown vertically into the air. At the top of its path, its acceleration in meters per second per second is
9.8
A small ball tied to a string swings without air resistance, beginning fromrest at point A. The string snags on a nail at point P, causing the ball to movein a small circle. The ball has maximum potential energy at point
A
Both a transverse wave and a longitudinal wave have
A.speed. B.wavelength. C.amplitude. D.frequency.
Which temperature scale has the smallest sized degrees
Fahrenheit
Which is most responsible for Earth's ocean tides?
Moon
Which pulls on the oceans of Earth with a greater force?
Sun
A good heat conductor is
a poor insulator.
The famous Leaning Tower of Pisa doesn't topple over because its center of gravity is
above a place of support.
Magnetic fields are produced by
all moving electrical charges
Some of a wave's energy dissipates as heat. In time, this will reduce the wave's
amplitude
The source of electrons that illuminate a common lamp in your home is
atoms in the lamp filament.
Like kinds of magnetic poles repel while unlike kinds of magnetic poles
attract.
A very massive object A and a less massive object B move toward each other under the influence of gravity. Which force, if either, is greater?
both forces are the same.
A ball rolls off the edge of a table at the same time another ball drops vertically from the same table. The ball to hit the floor first is the
both hit at the same time
Toss a baseball bat into the air and it wobbles about its
center of mass.
A coin and a ring roll down an incline at the same time. The one to first reach the bottom is the
coin
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 region of expanding air tends to
cool.
Newton's law of cooling applies to objects undergoing
cooling and warming
A car travels in a circle with constant speed. The net force on the car is
directed towards the center of the curve.
2 measurements necessary for calculating average speed are
distance and time
An object is propelled along a straight-line path by a force. If the net force were doubled, the object's acceleration would
double
Two protons attract each other gravitationally and repel each other electrically. The stronger of these two forces is
electrical.
Lillian safely touches a 100,000-volt Van de Graaff generator. Although the voltage is high, the relatively small amount of charge means a relatively small amount of
energy transfer.
When you touch a cold piece of ice with your finger, energy flows
from your finger to the ice.
To become a negative ion, an atom must
gain of an electron
A good absorber of radiation is a
good emitter of radiation
If you thrust a magnet into a closed loop of wire, the loop will
have a current in it.
An upright broom is easier to balance when the heavier end is
highest, farthest from your hand.
in science an educated guess is a
hypothesis
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.
Which horse moves faster in m/s on a merry-go-round?
one near outer rail
According to Newton, when the distance between two interacting objects doubles, the gravitational force is
one-quarter.
The fastest moving planet in a solar system is the
planet nearest the Sun.
Buoyant force acts upward on a submerged object because
pressure against its bottom is greater than pressure against its top
The planet Earth loses heat primarily by
radiation
When an ice cube in a glass of water melts, the water level
remains 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.
A torque acting on an object tends to produce
rotation
The source of all waves is
something that vibrates.
When an object is raised above the ground it gains a certain amount of potential energy. If the same object is raised twice as high it gains
twice as much potential energy.
A 1000-kg car and a 2000-kg car are hoisted the same distance in a gas station. Raising the more massive car requires
twice as much work.
Tidal forces in general are the result of
unequal forces acting on different parts of a body.
When sound travels faster near the ground than above, bending of sound tends to be
upward
Imagine a coil of wire laying flat down on on your desk and that a current is flowing through it in a counter clockwise (CCW) direction. The magnetic field in the center of the coil will be directed
upward from the desk.
An efficient step-up transformer increases
voltage
To think of electric potential difference we are thinking about
voltage.
A completely submerged object always displaces its own
volume of fluid.
Sound travels faster in air if the air temperature is
warm
The force required to maintain an object at a constant velocity in free space is equal to
zero
When a twirling ice skater brings her arms inward, her rotational speed
increases
A block of Styrofoam floats on water while a lead block of the same size block lies submerged in the water. The buoyant force is greatest on the
lead.
The white-hot sparks from a 4th-of-July-type sparkler that strike your skin transfer
little energy to you in spite of their high temperature.
The primary of a transformer is the coil connected to
the input power line.
Compared to a bar of pure gold, the density of a pure gold ring is
the same
A Mack truck and a Volkswagen traveling at the same speed collide head-on. The impact force is
the same for both.
Compared to the primary voltage, the secondary voltage can be
the same, higher, or lower
Particle A has twice the charge of nearby particle B. Compared to the force on Particle A, the force on Particle B is
the same.
A 1000-kg car moving at 10 m/s brakes to a stop in 5 s. The average braking force is
2000 N.
A ball player wishes to determine pitching speed by throwing a ball horizontally from an elevation 5 m above ground level. The ball lands 20 m downrange. The player's pitching speed is about
20m/s
The voltage across the input terminals of a transformer is 120 V. The primary has 25 loops and the secondary has 50 loops. The voltage the transformer delivers is
240V
if a baseball being thrown goes from zero to 30 m/s in 0.1 second, what is its average acceleration?
300 m/s/s
A 5-kg fish swimming at a speed of 1 m/s swallows an absent-minded 1-kg fish at rest. The speed of the larger fish after lunch is
5/6 m/s
A projectile is launched vertically upward at 50 m/s. If air resistance is negligible, its speed upon returning to its starting point is
50 m/s.
A small ball tied to a string swings without air resistance, beginning fromrest at point A. The string snags on a nail at point P, causing the ball to movein a small circle. The ball has maximum speed at point
B
If a piece of sheet metal is cut into the shape shown, its center of gravity is at
D
A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is
doubled.
Conducting materials are composed of atoms with
loose outer electrons.
Power is transmitted at high voltages because the corresponding current in the wires is
low so that overheating of the wires is minimized.
An object maintains its state of motion because it has
mass
When two lamps are connected in series to a battery, the electrical resistance of the circuit is
more than the resistance of either lamp.
An object that has kinetic energy must be
moving.
On some early automobiles both headlights failed when one bulb burned out. The headlights were likely connected in
series.
Which of these is a longitudinal wave?
sound
An iron nail is more strongly attracted to the
south or North Pole of a magnet
The magnetic north pole of the Earth is located near the geographic
south pole.
A substance with a high thermal inertia has a high
specific heat capacity.
Sound travels fastest in
steel
The rotational inertia of your leg is greater when your leg is
straight
It is correct to say that impulse is equal to
the change in momentum.
In order to catch a ball, a baseball player extends the hand forward before impact with the ball and then lets it ride backward in the direction of the ball's motion upon impact. Doing this reduces the force of impact on the player's hand principally because the
time of impact is increased.
Sound waves can interfere with one another so that no sound results.
true