Mechanics Test

1.)What does velocity specify that speed doees not?
Direction
Speed
Mass
2.)What is the aceleration of an object that increases its speed from 0-10 km/s in 10s?
10 km/s2
0 km/s2
1 km/s2
3.)You throw a rock from a cliff, and see it hit the ground 5 s later. What was the speed of the rock when it hit the ground? How far had it fallen?
s=49 m/s, d=61.25 m
s=10 m/s, d=50 m
s=100m/s, d=1000m
4.)If an airplane is traveling at 100km/hr through the air and there is a wind of 100 km/hr blowing at exactly right angles to it, how fast is the plane moving?
70.1 km/hr
141.4 km/hr
200 km/hr
5.)A projectile falls beneath the straight line path it would follow if there was no gravity. How far does it fall beneath this line if it has been travelling for 2s?
4.9 m
9.8 m
19.6 m
6.)True or False: Changes in the vertical component of velocity are proportional to changes in the horizontal component of velocity.
True
False
7.)If the mass of an object being acted on by a force is quadrupled while the force remains constant, by how much does the aceleration decrease?
Decreases by a factor of 4
Decreases by a factor of 2
Increases by a factor of 4
8.)What is the net force on an object in mechanical equilibrium?
0 N
1 N
9.8 N
9.)A baseball bat hits a ball and slows down. What force ahs caused this deceleration?
The force of gravity.
A force exerted by the ball on the bat.
A force exerted by the batter's arm on the bat.
10.)Which has the greater momentum:
A truck at rest
A fly moving at 1 km/hr
11.)What is the definition of impulse?
Impulse=ma
Impulse=vt
Impulse=Ft
12.)A gun initially at rest fires a bullet. What is the net momentum of the system after the bullet is fired?
100
0
-100
13.)How many joules of work are done when a 1 N force moves an object 3m?
1 J
4 J
3 J
14.)What is it that a body having energy is capable of doing?
Work
Physics
Yardwork
15.)How many joules of potential energy does a 1 kg object elevated 4 m gain?
5 J
3 J
4 J
16.)Which has more kinetic energy:
A car traveling at 60 mph
A half as heavy car traveling at 120mph
17.)Which of these quantities can a machine not multiply:
Input Enery
Input Force
Input Distance
18.)What two quantities does rotational inertia depend on?
Mass and the distribution of mass
Mass and the speed of the object
Weight and the speed of the object
19.)What is the name given to a force ht makes an object rotate?
Spin
Torque
Impulse
20.)Why is centrifugal force misnamed?
It is the same as centripetal force.
The word "centrifugal" means the opposite of what centrifugal force is.
It is not a force.
21.)If the distance between two objects is quadrupled, by how much does the gravitational force between them decrease?
Decreases by a factor of 2
Decreses by a factor of 4
Decreases by a factor of 16
22.)What does the fact that G is so small mean about the gravitational force?
It is a strong force
It is a weak force
23.)If the distance between two objects is quadrupled, by how much does the tidal force beween them decrease?
Decreases by a factor of 4
Decreases by a factor of 16
Decreases by a factor of 64