Simple Harmonic Motion and Waves
Multiple Choice Questions
Choose the correct answer.
- A transverse wave on a string has an amplitude A. A tiny spot on the string is colored red. As one cycle of the wave passes by, what is the total distance traveled by the red spot?
| A. A | B. 2A | C. ½ A | D. 4A |
Hint: In a journey of one cycle, the oscillator travels the amplitude for four times.
- Which of the following does not affect the period of the mass-spring system?
| A. mass | B. spring constant | C. amplitude of vibration | D. All of the above affect the period |
Hint: 
- An object of mass m oscillates on the end of a spring. To double the period, replace the object with one of mass:
| A. 2m | B. m/2 | C. 4m | D. m/4 |
Solution:
Therefore, for T =2T, m = 4m.
- A car mounted on shock absorbers is like a mass on a spring. If we ignore damping, how will the frequency of the oscillations change if passengers (or a heavy load) are added to the car? The frequency will
| A. increase | B. decrease | C. stay the same | 4. be zero |
Hint: 
, therefore, 
- If the pendulum completes exactly 12 cycles in 2.0 min, what is the frequency of the pendulum?
| A. 0.10 Hz | B. 0.17 Hz | C. 6.0 Hz | D. 10 Hz |
Hint: 12 cycles completed in 2.0 min = 120 s.
- A certain pendulum has an iron bob. When the iron bob is replaced with a lead bob of the same size, its time period will
| A. stay the same | B. decrease | C. increase | D. be zero |
Hint: Density of iron (7.874 g/cm3) is less than density of lead (11.34 g/cm3). Therefore, when sizes are same, mass of lead bob > mass of the iron bob. Since, T=2π(l/g)1/2, therefore, the time period of the pendulum does not depend on the mass of the bob and the time period of the pendulum will not change.
- A wave transports
| A. Energy but not matter | B. matter but not energy | C. both energy and matter | D. air |
- The bending of wave around the edges of the obstacle is
| A. reflection | B. refraction | C. diffraction | D. damping |