PART A. MULTIPLE CHOICE:

Select the letter of the BEST ANSWER and place it in the grid provided

1. A car travelling east at 40 m/s came to rest 8.0 s after the brakes were applied. The average acceleration during the 8.0 s interval was:

a) 5.0 m/s2  [E]           b) 5.0 m/s2  [W]         c) 2.5 m/s2  [E]        d) 2.5 m/s2  [W]    e) 0.2 m/s2  [W]

2.  A baseball is thrown vertically into the air.  The instantaneous acceleration of the ball at its highest point is:

a) zero                           b) changing from 9.8 m/s2 [up] to 9.8 m/s2 [down]

c) 9.8 m/s2 [up]            d) 9.8 m/s2 [down]

3. Which graph is correct for a cart rolling down a uniform ramp?

(Let “DOWN the ramp” be positive.)

4. Which graph is correct for a ball thrown up in the air?  The motion ends when it reaches its maximum height. (Let “UP” be positive.)

t

b) d

t

c) d

d) v

t

5. A jogger jogs 300 m [W], 200 m [N], then 300 m [E]. The magnitude of the jogger’s displacement is:

a) 800 m                        b) 300 m                        c) 200 m                        d) 100 m

6. A 90 g apple is located 2.2 m below the top of an apple tree.  What is the gravitational potential energy of the apple with respect to the top of the tree?

a) 1.96 x 104 J               b) ‐ 1.96 x 104 J            c) 1.9 J              d) ‐ 1.9 J

7. Acceleration is ALWAYS in the same direction as the:

a) displacement           b) initial velocity          c) final velocity             d) net force

8. The kinetic energy of a 50 kg bike that moves 40 m in 10 s at constant speed is:

a) 1.96 x 105 J               b) 500 J            c) 400 J             d) 100 J

9. A light ray strikes a plane mirror at an incident angle of 20O.  The angle between the incident and reflected light is:

a) 20O

b) 40O

c) 90O

d) 140O

10. The period of a heart beating 72 times per minute is:

a) 72 s               b) 1.2 s             c) 0.83 s           d) 0.014 s

11. Which of following wave characteristics is completely independent of the others?

a) frequency    b) wavelength              c) speed           d) period          e) amplitude

12. This diagram shows two pulses travelling towards each other.

Which best represents their resultant?

b)

13. To compare the brightness of any two bulbs in a complex circuit, you would have to calculate the ___________________ of each.

a) power                        b) current                     c) voltage         d) resistance

14. The rate of flow of charge in a circuit is known as:

a) power                        b) voltage                      c) current         d) electrical energy

15. A 50 Ω light bulb drawing 0.80 A for 30 s consumes _______________ Joules of energy.

a) 1200             b) 960               c) 40                  d) 32

Please put your answers to the multiple choice questions in the respective box below:

PART B: SHORT ANSWER: All steps must be shown for consideration

1. A person applies a 220 N horizontal force to a 55 kg crate to push it across a level floor.  The coefficient of kinetic friction is 0.37.                             * Draw a Free body diagram

a) What is the force of friction?

b) What is the acceleration of the crate?

2. Two blocks M1 and M2 are connected by a

massless string that passes over a massless pulley as

shown in the figure. M2, which has a mass of 11.5 kg,

rests on a long ramp of angle = 27°

Friction can be ignored in this problem. Find the

value of the mass M1 for which the two blocks are in

equilibrium (i.e. not accelerating).

3. A boy throws a baseball vertically upward with an initial speed of 6.30 m/s.  It rises to a point

1.30 m above the release point.  How fast is the ball moving at 1.30 m?  Note: it is not necessarily the highest point.                                  Hint: Use conservation of energy

Diagram:

4. Determine the missing values in this circuit, noting that R1 and R2 are equal resistors and the current at point 2 is 2 A and the voltage at the source is 70V.

R stands for resistance in ohms, V is potential in volts, I is current in amps