Physics 201 MWF10:20 Fall 1995 (Ford)
Exam I Chapts. 1-5 in SZY College Physics

Show all your work. Partial credit will be given if earned. Write your answers in the blanks provided. The formula sheet is the last page of the exam. It can be torn off from the rest of the exam and doesn't have to be turned in.


(16 pts) 1. Vectors A and B are given in the sketch.

a) What are the x and y components of the vector A?

Ans. A_x = __________________

A_y = __________________

b) What are the magnitude and direction (angle ) measured counterclockwise from the +x-axis) of the vector C that is the sum of the vectors A and B shown in the sketch (C = A + B)?

Ans. C =_______________

= ________________


(20 pts) 2. A small rock is thrown straight up from the roof of a building. The rock has an initial speed of v₀ = 15 m/s. The rock strikes the ground 6.0 s after being thrown.

a) What is the magnitude of the velocity of the rock when it is at its maximum height above the roof?

Ans. _____________________________

b) What is the acceleration (magnitude and direction) of the rock when it is at its maximum height above the roof?

Ans. a = ___________________

direction = ________________________

c) What is the height of the building?

Ans. __________________________


(21 pts) 3. A small cube of ice slides off a horizontal tabletop with an initial velocity that is horizontal and has magnitude 8.0 m/s as leaves the tabletop. The tabletop is a vertical distance of 4.9 m above the floor.

a) How much time does it take for the ice cube to reach the floor?

Ans. ________________

b) What is the horizontal distance from the edge of the tabletop to the point where the ice cube hits the floor.

Ans. _________________

c) What are the horizontal and vertical components of the velocity of the ice cube just before it strikes the floor?

Ans. horizontal = _______________________

vertical = ____________________


(21 pts) 4. A block with mass m = 2 kg is released at the top of an inclined plane that has slope angle = 37°. The block has an acceleration of a = 5.0 m/s² as it slides down the incline.

a) What is the normal force exerted by the incline on the block as it slides down?

Ans. __________________________

b) What is the friction force exerted by the incline on the block as it slides down?

Ans. ______________________

c) What is the coefficeint of kinetic friction µ_k between the block and the incline?

Ans. ______________________________

(22 pts) 5. A 4.0 kg block on a horizontal tabletop is connected by a massless rope that passes over a massless, frictionless pulley to a hanging block of mass m. The coefficient of kinetic friction between the 4.0 kg block and the tabletop is µ_k = 0.2. When the blocks are released, the hanging block descends with an acceleration of 3.0 m/s².

a) While the blocks are moving, what is the magnitude of the friction force on the 4.0 kg block?

Ans. __________________________

b) While the blocks are moving, what is the tension in the rope that connects the two blocks?

Ans. ___________________

c) What is the mass m of the hanging block?

Ans. ___________________