2-D AP Physics Handout
88b5. A 2-kilogram block rests at the edge of a platform that is 10 meters above level ground. The block is launched horizontally
from the edge of the platform with an initial speed of 3 meters per second. Air resistance is negligible. The time it will take for the
block to reach the ground is most nearly
(A) 0.3 s
(B) 1.0 s (C) 1.4 s
(D) 2.0 s
(E) 3.0 s
88b9. A diver initially moving horizontally with speed v edives off the edge of a vertical cliff and lands in the water a distance d
from the base of the cliff. How far from the base of the cliff would the diver have landed if the diver initially had been moving
horizontally with speed 2v?
(A) d
(B)
2d
(C)2d
(D)4d
(E) can’t be determined without knowing the height of the cliff
88b62. A truck traveled 400 meters north in 80 seconds, and then it traveled 300 meters east in 70 seconds. The magnitude of the
average velocity of the truck was most nearly
(A) 1.2 m/s
(B) 3.3 m/s
(C) 4.6 m/s
(D) 6.6 m/s
(E) 9.3 m/s
88b63. A projectile is fired with initial velocity vo at an angle 0 with the horizontal and follows the trajectory shown above. Which
of the following pairs of graphs best represents the vertical components of the velocity and acceleration. v and a, respectively, of
the projectile as functions of time t?
Questions 64-66
A ball is thrown and follows the parabolic path shown above. Air friction is negligible.
Points P and R are the same height above the ground.
93b64. How do the speeds of the ball at the three points compare?
(A) vp < vQ < vR
(B) vR < vQ < vP (C) vQ < vR < vP
(D) vQ< vP = vR
Point Q is the highest point on the path.
(E) vP = vR < vQ
93b65. Which of the following diagrams best shows the direction of the acceleration of the ball at point P ?
(A)
(B)
(C)
(D)
(E)
93b66. Which of the following best indicates the direction of the net force, if any, on the ball at point Q ?
(A)
(B)
(C)
(D)
98b57. A ball of mass 0.4 kg is initially at rest on the ground. It is kicked and leaves the kicker's foot with a speed of 5.0 m/s in a
direction 60° above the horizontal. The magnitude of the impulse imparted by the ball to the foot is most nearly
a. 1 N s
b.
3 Ns
c. 2 N s
d.
2
3
Ns
e. 4 N s
Questions 59-60
A rock of mass m is thrown horizontally off a building from a height h, as shown above. The speed of the rock as it leaves the
thrower’s hand at the edge of the building is v0.
98b59. How much time does it take the rock to travel from the edge of the building to the ground?
a.
hv o
b.
h
v0
c.
hv 0
g
d.
2h
g
e.
2h g
1984B1. A ball of mass M attached to a string of length L moves in a circle in a vertical plane as shown above.
At the top of the circular path, the tension in the string is twice the weight of the ball. At the bottom, the ball
just clears the ground. Air resistance is negligible. Express all answers in terms of M, L, and g.
a. Determine the magnitude and direction of the net force on the ball when it is at the top.
b. Determine the speed vo of the ball at the top.
The string is then cut when the ball is at the top.
c. Determine the time it takes the ball to reach the ground.
d. Determine the horizontal distance the ball travels before hitting the ground.
1992B1. A 0. 10-kilogram solid rubber ball is attached to the end of an 0.80-meter length of light thread. The
ball is swung in a vertical circle, as shown in the diagram above. Point P, the lowest point of the circle, is 0.20
meter above the floor. The speed of the ball at the top of the circle is 6.0 meters per second, and the total
energy of the ball is kept constant.
a. Determine the total energy of the ball, using the floor as the zero point for gravitational potential energy.
b. Determine the speed of the ball at point P, the lowest point of the circle.
c. Determine the tension in the thread at
i. the top of the circle;
ii. the bottom of the circle.
The ball only reaches the top of the circle once before the thread breaks when the ball is at the lowest point of
the circle.
d. Determine the horizontal distance that the ball travels before hitting the floor.
1994B1. A ball of mass 0.5 kilogram, initially at rest, is kicked directly toward a fence from a point 32 meters
away, as shown above. The velocity of the ball as it leaves the kicker's foot is 20 meters per second at an
angle of 37° above the horizontal. The top of the fence is 2.5 meters high. The kicker's foot is in contact with
the ball for 0.05 second. The ball hits nothing while in flight and air resistance is negligible.
a. Determine the magnitude of the average net force exerted on the ball during the kick.
b. Determine the time it takes for the ball to reach the plane of the fence.
c. Will the ball hit the fence? If so, how far below the top of the fence will it hit? If not, how far above the top
of the fence will it pass?
d. On the axes below, sketch the horizontal and vertical components of the velocity of the ball as functions
of time until the ball reaches the plane of the fence.