This exam consists of 25 questions; true-false questions are worth 2 points each, three-choice multiple choice questions are worth 3 points each, five-choice multiple choice questions are worth 6 points each. The maximum possible score is 111. When the exam was given, the mean was 91.5; the median was 95. Click here to see the formula sheet that came with the exam.

A 10 kg box initially stands still on a horizontal frictionless surface. A force F = 15 N is applied horizontally to the box, and the box moves 25 m. What is the work done on the box by the force F ?

(a) 0 J (b) 150 J (c) 375 J (d) 425 J (e) 1250 J

(a) 2.4 m/s (b) 8.7 m/s (c) 15.0 m/s (d) 25 m/s (e) 27.4 m/s

(a) smaller. (b) the same. (c) greater.

A basketball of mass 0.5 kg is released from rest at an initial height of 2 m above the floor. It falls, hits the floor, and bounces back up to a maximum height of 1.2 m above the floor.

What is the work W_{g} done by gravity on the ball as it falls from its initial height down to a point just before it hits the floor?

(a) W_{g} = 0 J (b) W_{g} = 1 J (c) W_{g} = 4.9 J (d) W_{g} = 9.8 J (e) W_{g} = 19.6J

(a) ΔKE = W_{g} (b) ΔKE = -W_{g} (c) ΔKE = 0

(a) 0 J (b) 1 J (c) 3.9 J (d) 7.8 J (e) 9.8 J

A car of mass 1500 kg collides head-on with a truck of mass 9000 kg. After the collision, the wreckage is at rest. The speed of the car just before the collision was 30 m/s. What was the speed of the truck just before the collision?

(a) 5 m/s (b) 10 m/s (c) 15 m/s (d) 30 m/s (e) 60 m/s

(a) I_{C} = I_{T} (b) I_{C} = 6 I_{T} (c) I_{C} = I_{T} / 6

(a) 2 gm (b) 5 gm (c) 12 gm (d) 21 gm (e) 25 gm

After the force acts, which block has the larger momentum?

(a) The block of mass M. (b) The block of mass 2M. (c) The two blocks have the same momentum.

A ball of mass M is released from rest a height H above a horizontal floor. It hits the floor and bounces back up to its original height H. What is the magnitude of the impulse exerted by the floor on the ball during the collision?

(a) M sqrt(2gH) (b) 2M sqrt(2gH) (c) 0

(a) the same. (b) greater. (c) less.

What is the speed of block 1 after the collision?

(a) v_{1,f} = 0 m/s (b) v_{1,f} = 5 m/s (c) v_{1,f} = 10 m/s (d) v_{1,f} = 15 m/s (e) v_{1,f} = 20 m/s

(a) 30 kg-m/s (b) 35 kg-m/s (c) 40 kg-m/s (d) 45 kg-m/s (e) 50 kg-m/s

A 60 kg skier slides down a gentle slope with a constant velocity. The length of the slope is 1 km, and the vertical drop is 200m (see picture).

In going from the top of the hill to the bottom, the total work done on the skier by all forces is

(a) positive. (b) negative. (c) zero.

(a) W_{f} = 0 (b) W_{f} = 1.2 × 10^{5} J (c) W_{f} = 5.9 × 10^{5} J (d) W_{f} = -1.2 × 10^{5} J (e) W_{f} = -5.9 × 10^{5} J

A car drives on a straight horizontal road and its wheels roll on the ground without slipping. The radius of the front wheels is R_{front } = 0.30 m and the radius of the rear wheels is R_{rear} = 0.35 m. The front wheels rotate with an initial angular velocity of ω_{F0} = 88 rad/s.

What is the initial speed of the car?

(a) 18.3 m/s (b) 26.4 m/s (c) 32.8 m/s (d) 61.7 m/s (e) 88.0 m/s

(a) makes more than one revolution. (b) makes less than one revolution. (c) also makes exactly one revolution.

What is the angular velocity of a front wheel at t = 1 s ?

(a) 33 rad/s (b) 44 rad/s (c) 55 rad/s (d) 66 rad/s (e) 77 rad/s

A uniform plank and a bowling ball have the same mass M. The length of the plank is 5m and it rests horizontally on two supports, as shown in the drawing, with 2m of the plank hanging over the right support.

To what distance x_{tip} (measured from the right-most support) can the bowling ball be rolled onto the overhanging part of the plank before the plank just begins to tip?

(a) x_{tip} = 0.3 m (b) x_{tip} = 0.5 m (c) x_{tip} = 0.7 m (d) x_{tip} = 0.8 m (e) x_{tip} = 0.9 m

(a) 0 (b) Mg (c) 2Mg

One end of a massless horizontal beam is attached to a vertical wall by a hinge, and the other end is supported by a string which is also attached to the wall. In case 1, as shown in the figure, a ball of mass M is hung from the end of the beam, while in case 2, an identical ball is hung from the middle of the beam.

How does the tension in the string attached to the wall compare between the two cases?

(a) T_{1} > T_{2} (b) T_{1} < T_{2} (c) T_{1} = T_{2}

(a) T_{2} = Mg / 2 (b) T_{2} = Mg (c) T_{2} = 2 Mg