Physics asap : ( 90 pts
1.which situation is the best example of inertia?
a) an old lady uses a walker and is able to cross the street.
b) a rocket thrusts its boosters and lifts off the launching pad.
c) a rock is thrown vertically up in the air and it falls back to the earth.
d) you go down a steep roller coaster and it feels like your stomach is going up into your throat.

2. a 10.0 kilogram mass of iron on earth exerts a downward force of 98 newtons. on the moon this same 10.0 kilograms of iron is weighed and found to exert a downward force of 16.3 newtons. how is this possible?
a) the earth is farther away reducing the pull.
b) weight is the same everywhere, but mass changes.
c) mass begins to evaporate in the vacuum of space.
d) the gravity on the moon is one sixth the gravity of earth.

3.your little brother holds a 2 kg water balloon over the railing of his 15 m high tree house. what is the gravitational potential energy of the water ballon?
a) 2kg x 9.8 m/s2 x 15m
b) 2kg x 15m
c) 2kg + 9.8 m/s2 + 15m
d) 2kg x 15m + 9.8 m/s2

4. which is the correct free body diagram for a box being pushed across a smooth frictionless level floor?
a) a
b) b
c) c
d) d

* hover over answer image to enlarge

5. the diagram shows a 15-kg box resting on a wedge which has an angle of inclination of 30° and a coefficient of friction of 0.15. find the value of the vector fg.
a) 22.07 n
b) 147.15 n
c) 245.23 n
d) 355.35 n

6. why does a raindrop accelerate as it falls to the earth?
a) because it gains mass during its travel
b) because the force of gravity pulls on the drop
c) because it gets further from the cloud where it started
d) because fewer forces are present to slow it down as it drops

7)
which of these would be the best example of unbalanced forces?
a) a dog runs at a constant velocity.
b) you stand very still during the national anthem.
c) a snowball picks up speed as it rolls down the mountain.
d) your coffee cup does not move from its original spot on the desk.

8)
astronauts appear weightless while working in the international space station because
a) they are in a state of free fall.
b) there isn't any gravity in outer space.
c) they have very little mass when in outer space.
d) they have gravitational attractions to the sun and moon.

9)
between which pair of objects would the largest gravitational attraction be found? assume there is an equal distance between the first and second items mentioned in all four answer choices?
a) an ant and the earth
b) a person and the earth
c) a person and a small bird
d) a small bird and the earth

10)
a 5-kg object experiences forces as shown in the diagram. which statement best describes the motion of the object?
a) the object would have a velocity of 6 m/s to the left.
b) the object would have a velocity of 6 m/s to the right.
c) the object would have an acceleration of 6 m/s/s to the left.
d) the object would have an acceleration of 6 m/s/s to the right.

11)
two platoons line up for a tug of war. if both platoons have the same number of participants on a team, what other factor is critical to either platoon's win?
a) age of men
b) height of men
c) total mass of the team
d) condition of the ground

12)
in which of these examples would the net force be zero?
a) a bullet is shot out of a gun
b) a skydiver jumps out of a airplane at 3000 feet
c) your new car accelerates from 0-16 in 4.5 seconds
d) you run at a constant velocity of 5.0 miles per hour

13)
there are four forces acting on the box: a spring pulls with a force of 40 n. the force of gravity acts downward; and the force of the table is pushing up on the box. what must be true of the frictional force if the box moves across the table?
a) it is equal to the effort force.
b) it is less than the effort force.
c) it is more than the effort force.
d) it is equal to the force of gravity.
14)

14.the free body diagram represents silly sally hanging from a trapeze bar. sally weighs 660 newtons. what is the force in each of the chains holding the trapeze bar?
a) 185n
b) 330n
c) 660n
d) 1320n

15)
as an airplane files, the airplane pushes against air. this resistance is called drag. what force does drag work against?
a) energy
b) lift
c) thrust
d) weight