EXAM 1                      October 2, 1996                          PHYS 207 


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g = 9.8 m/sec2Radius of the earth = 6.38 x 106 m The mass of the electron is 9.11 x 10-31 kg.
Calculus and trig formulas will not be given after this exam:
cos(2x) = cos2 (x) - sin2 (x)sin(2x) = 2 sin(x) cos(x) d xn / dx = n xn-1
d cos(x)/dx = - sin(x) d sin(x)/dx = cos(x) d(fg)/dx = f (dg/dx) + (df/dx) g
For all problems, place the equations representing the physics principles you are using in the box on the page. You may use the general form of the equation or the form you get applying the principle to the problem at hand. If no diagram is applicable to a problem, write "none" in the diagram section.

1. (10 points)

(a) Explain how to remember the equations for motion in one dimension under constant acceleration.
(b) Mark on the diagram below all points where vx is a maximum or a minimum and all points where vx = 0.

2. (From homework; 30 points) Calculate the acceleration of a person at latitude 40o owing to the rotation of the Earth. 

 
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3. (30 points) A proton moving with speed 1 x 107 m/sec passes through a 0.020 cm thick piece of paper and emerges with a speed of 2 x 106 m/sec. Assuming uniform deceleration, find the deceleration and the time taken to pass through the paper. 

 
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4. (30 points) A boy stands at the peak of a hill which slopes downward uniformly at an angle phi .

(a) If he throws a rock at an angle theta above the horizontal, how far will it have gone horizontally when it hits the slope?

(b) At what angle must he throw the rock so that it has the greatest range? 

 
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Use this page if necessary to continue any of the problems. Be sure to label the problem number.