Version B

1. A bridge piling has an area of 1.25 m². It supports 1875 N. Find the stress on the column.

a) 1875 N/m² b) 1875 N c) 1500 N/m² d) 2344 N/m²  

a) 10 m b) 0.01 m c) 1.0 m d) 0.10 m

3. A brick weighs 50 N, and measures 30 cm x 10 cm x 4 cm. What is the maximum pressure it can exert when placed on a horizontal surface?

a) 16.3 kPa b) 41.7 kPa c) 4.17 kPa d) 1.67 kPa e) 12.5 kPa

4-7. A discouraged gambler in a casino takes a die (half of a pair of dice) and a scrap of thread out of his pocket. He ties the thread around the die and dips it into a fish tank filled with water. The 13.6 gram cubical die measures 2 cm on an edge. (see sketch)

4. As the die is lowered into the tank, the pressure on the upper surface of the die increases by 735 Pa. The die must be _____ cm below the water surface.

a) 0.735 b) 0.133 c) 7.5 d) 75 e) 5.0

5. The specific gravity of the die is

a) 16.66 b) 5.76 c) 0.588 d) 1.7 x 10⁶ e) 1.7

6. The buoyant force on the die is 0.0784 N and is directed up. The buoyant force on the die would be larger if:

a) the die was farther below the water surface.

b) the density of the die was smaller.

c) the density of the water was greater.

d) All of the previous are true.

e) the die was oriented so a corner points straight up.

7. The tension in the thread is _____ N.

a) 0.0784 b) 0.0136 c) 0.1333 d) 133.28 e) 0.0549

8-10. Water for a fountain passes through of a horizontal feeder pipe connected to a 3 m long vertical riser pipe that ends in a nozzle. The water passes through the nozzle and sprays up into the air. (see sketch) At points A and C the pipe has a diameter of 2.5 cm and at point B the pipe has a diameter of 5.0 cm. The water has a velocity of 3.5 m/s at point A and moves frictionlessly through the pipes.

8. The velocity of the water is _____ m/s at point B.

a) 1.75 b) 6.13 c) 0.88 d) 3.50 e) 1.14

9. Point C, at the end of the 2.5 cm diameter nozzle, is open to the atmosphere. The gauge pressure at point A is _____ kPa. (Hint: First ask yourself what the water velocity is at point C?)

a) 130.7 b) 29.4 c) 6.13 d) 101.3 e) 71.9

10. The pressure at point B is _____ the pressure at point A.

a) greater than b) less than c) the same as

11. The big football game played next Sunday is called

a) the cereal bowl b) bowling for dollars. c) the toilet bowl. d) the fruit bowl

e) the Super Bowl!!!!!!!

12-18. A 50 gram mass attached to an ideal spring (k = 5.48 N/m) oscillates in simple harmonic motion when displaced horizontally and released. (see sketch)

12. The time at point A on the time axis of the graph should be _____ s.

a) 3.33 b) 1.67 c) 0.07 d) 0.30 e) 0.60

13. The maximum acceleration of the mass is _____ m/s².

a) 0.13 b) 7.67 c) 3.91 d) 1.40 e) 0.38

14. The maximum speed of the oscillating mass is _____ m/s.

a) 0.44 b) 0.73 c) 0.20 d) 7.67 e) 0.54

15. When the mass passes through the equilibrium position, the _____ of the oscillator is a maximum.

a) velocity b) acceleration c) potential energy d) amplitude e) total energy

16. The frequency of this oscillator will increase if the _____ increases.

a) maximum velocity b) amplitude c) spring constant d) period e) mass

17. The position of the mass at any time may be calculated using the formula x =

a) -A sin w t b) +A sin w t c) +A cos w t d) -A cos w t

18. When you take this oscillator to the moon where g is smaller than on Earth, the frequency will _____ .

a) increase b) remain the same c) drop

19. A simple pendulum, consisting of a 0.25 kg mass attached to a long massless string, swings back and forth with a frequency of 2 Hz. What frequency (in Hz) would have resulted if a 0.50 kg mass had been attached to the string instead?

a) 1.41 b) 1 c) 0.707 d) 0.5 e) 2

20. The most effective way to change the period of a pendulum is to change its