This exam consists of 26 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 110. When the exam was given, the mean was 88.0 the median was 90. Click here to see the formula sheet that came with the exam.

A man can swim with a speed of 3 m/s in still water. He crosses a river of width 100 m by swimming in the direction that will take him across in the smallest possible time. When he reaches the opposite shore, he has been swept 50 m downstream. How fast is the river flowing?

(a) 1.5 m/s (b) 2.5 m/s (c) 4 m/s (d) 5 m/s (e) 6 m/s

(a) 44.7 s (b) 100 s (c) 115 s (d) 192 s (e) 203 s

(a) T > W (b) T = W (c) T < W

(a) 1 N (b) 2 N (c) 3 N (d) 4 N (e) 5 N

A 10 kg box is sliding with constant velocity down a ramp that makes an angle of 10° with the horizontal. What is the magnitude of the frictional force between the ramp and the box?

(a) 7 N (b) 17 N (c) 34N (d) 98 N (e) 10 3N

(a) 0 N (b) 12 N (c) 17 N

Two blocks, one of mass m and the other of mass 2m are connected to opposite ends of a string via a pulley, as shown in the figure. One block sits on a horizontal frictionless table and the other hangs vertically, with gravity pointing downward. The system is released from rest. What is the magnitude of the acceleration of the blocks?

(a) 3.27 m/s^{2} (b) 4.90 m/s^{2} (c) 7.35 m/s^{2} (d) 9.81 m/s^{2} (e) 12.3 m/s^{2}

(a) b > a (b) b = a (c) b < a

A cannon ball is fired from a cannon on the ground, and lands a distance of 4.65km away from the cannon 30 s after being fired, as in the figure.

What is the x-component of the initial velocity of the cannonball?

(a) 65 m/s (b) 155 m/s (c) 215 m/s

(a) 63 m/s (b) 85 m/s (c) 112 m/s (d) 147 m/s (e) 171 m/s

A truck is carrying a box. The coefficient of static friction is µ_{s} = 0.31 between the truck bed and the box. What is the maximum possible acceleration of the truck on a horizontal road without the box sliding?

(a) 2.0 m/s^{2} (b) 3.0 m/s^{2} (c) 4.0 m/s^{2}

Suppose that the truck is now moving downhill. How does the maximum possible acceleration compare to that in the preceding question?

(a) the same (b) larger (c) smaller

A bus is driving at a speed of 30 m/s. Its wheels have a radius of 0.5 m. How long does it take each wheel to turn exactly once?

(a) 0.1 s (b) 0.2 s (c) 0.5 s

(T) True (F) False

(a) 1998 m/s^{2} (b) 2190 m/s^{2} (c) 3939 m/s^{2} (d) 4190 m/s^{2} (e) 10110 m/s^{2}

(a) 1 s (b) 2 s (c) 4 s

(a) a_{s} = 9 a_{m} (b) a_{s} = 81 a_{m} (c) a_{s} = 729 a_{m}

(a) The normal force on the box is zero. (b) The acceleration of the box is zero. (c) The weight (force due to gravity) on the box is zero.

Last summer balloonist Steve Fossett managed to perform the first non-stop solo trip around the globe. His journey covered 31,290 kilometers (all in the southern hemisphere) in 14 days and 19 hours, all at nearly constant altitude.

What was Steve’s average speed during the trip?

(a) 10 km/hour (b) 33 km/hour (c) 55 km/hour (d) 88 km/hour (e) 99 km/hour

(a) 5 s (b) 6 s (c) 7 s (d) 15 s (e) 22 s

(a) 117 m/s (b) 177 m/s (c) 217 m/s

The distance versus time plot shown here describes the motion of a jogger during a work out. Based on this graph answer the following questions.

What is the average velocity of the runner during the work out?

(a) 0.5 miles/hour (b) 1 miles/hour (c) 2 miles/hour (d) 5 miles/hour (e) 6 miles/hour

(a) 10 miles/hour^{2} (b) 19 miles/hour^{2} (c) 21 miles/hour^{2} (d) 25 miles/hour^{2} (e) 44 miles/hour^{2}

On an aircraft carrier a steel cable is used to stop the landing jets. The distance between where the steel cable first hooks on to the jet and the end of the runway is 320 meters. Consider a jet landing at a speed of 60 meters/second with respect to the carrier.

Without the steel cable to slow it down, how long would it take the jet to travel the 320 meter long runway?

(a) 5.3 s (b) 44 s (c) 102 s

(a) 3.14 m/s^{2} (b) 8.57 m/s^{2} (c) 11.7 m/s^{2}

(a) ball A (b) ball B (c) They both hit the ground at the same time.