Download Forces and Motion Unit Pre Assessment

Forces & Motion Unit Pre-Assessment
Do NOT write on this!!
A. Multiple Choice- choose the best answer.
1. Which is an example of zero acceleration?
a. a bus coming to a stop
b. an ice hockey player turning around
c. a person walking on a treadmill at a steady rate.
d. an airplane speeding up along a runway
2. A change in position over time is called:
a. acceleration
b. motion
c. location
d. distance
3. You push two chairs in a straight line with the same force. One chair is more massive than the
other. The more massive chair will have:
a. greater acceleration
b. less acceleration
c. greater centripetal force
d. less centripetal force
4. Alison dives 5 meters below the surface of a lake. The pressure on her:
a. decreases because under water there is no air pressure
b. is directed upward because some objects are buoyant in water
c. is directed downward because air is less dense than water
d. increases because of the weight of all the water above her
5. A flat, or horizontal, line on a distance-time graph means that the speed is:
a. increasing
b. decreasing
c. higher than average
d. zero
6. A push or pull is called:
a. motion
b. force
c. acceleration
d. velocity
7. Jenna knows that a friend runs 100 m in 8 s. She could use this to calculate her friend’s:
a. position
b. motion
c. speed
d. acceleration
8. A skater is moving at a constant speed. How can he increase his speed?
a. drag the heel stop to increase friction
b. lean to one side, causing the skates to turn
c. reduce the force with which he pushes his feet against the ground
d. increase the force with which he pushes his feet against the ground
9. A collision is a situation in which two objects in close contact transfer:
a. Energy and mass
b. Energy and inertia
c. Energy and weight
d. Energy and momentum
10. Centripetal force keeps an object moving in a circle. This force points:
a. toward the center of the circle
b. toward the outer edge of the circle
c. to the right of the center of the circle
d. away from the circle in all directions
11. Speed in a specific direction is:
a. acceleration
b. distance
c. position
d. velocity
12. The strength of gravitational force between objects depends on:
a. mass and distance
b. pressure and area
c. mass and volume
d. force and acceleration
13. The upward force exerted on objects in a fluid is called:
a. displacement
b. hydraulics
c. buoyancy
d. density
14. To specify the position of an object, you need to know:
a. its motion
b. a reference point
c. its speed
d. a unit of measurement
15. Air resistance increases with:
a. increased speed and decreased surface area
b. decreased speed and increased surface area
c. increased speed and increased surface area
d. decreased speed and decreased surface area
16. Latitude and longitude measure:
a. position
b. motion
c. speed
d. direction
17. As Jimmy rubs a piece of wood with sandpaper, the wood becomes warmer. This release of
heat is due to:
a. air pressure
b. air resistance
c. friction
d. gravity
18. A person on a moving train sees a car that appears to be stopped. A person outside the train
sees both the car and the train moving. This example shows:
a. a unit of measurement
b. changing speed
c. relative motion
d. measurement of distance
19. The formula for calculating the force of gravity on a mass close to Earth’s surface is F=mg. The
g in the formula is:
a. the mass of the object in grams
b. the speed of the object as it falls
c. acceleration caused by Earth’s gravity
d. constant velocity caused by Earth’s gravity
20. Balanced forces act on:
a. two different objects
b. the same object
c. balanced objects
d. unbalanced objects
21. Action/reaction force pairs act on:
a. two different objects
b. the same object
c. balanced objects
d. unbalanced objects
22. Inertia is the resistance of an object to a change in its:
a. gravity
b. motion
c. mass
d. balanced force
23. Newton’s second law describes the relationship among:
a. acceleration, mass, and velocity
b. acceleration, mass, and force
c. velocity, force, and mass
d. mass, acceleration, and distance
24. When you push on a door, the door pushes back with an equal and opposite force. These two
forces are known as:
a. mass and velocity force pairs
b. unbalanced force pairs
c. mass and acceleration force pairs
d. action/reaction force pairs
25. According to Newton’s Laws of Motion:
a. Objects in motion will eventually stop
b. Force is related to mass and acceleration
c. Gravity is a force that exists only between really large masses
d. Sometimes action forces have equal reactions
B. Use the formula bank to solve the problems below. Make sure you use the correct unit of
measure!
Speed = d
t
Momentum = mv
Acceleration = Vf – Vi
t
Pressure = F
A
Force = ma
26. A man runs a distance of 6400 m in a race. If it takes him 800 seconds to run that distance,
what is his speed?
a. 5,600 m/s
c. 0.8 m/s2
2
b. 16 m/s
d. 8.0 m/s
27. A car has an initial velocity of 22 m/s and 2 seconds later has a velocity of 58 m/s. What is the
car’s acceleration?
a. 40 m/s2
c. 18 m/s2
b. 36 m/s2
d. -18 m/s2
28. A bowling ball with a mass of 6 kg leaves your hand with an acceleration of 20 m/s 2. What size
force did you apply?
a. 120 N
c. 26 N
b. 14 N
d. 33.3 N
29. A 40 kg person is running at 4 m/s. What is the person’s momentum?
a. 160 kg x m/s2
c. 36 kg x m/s2
b. 44 kg x m/s2
d. 10 kg x m/s2
30. If a winter hiker weighing 500N is wearing boots that have an area of 5m2, how much pressure
is exerted on the snow?
a. 2,500 Pa
c. 25 Pa
b. 100 Pa
d. 505 Pa