SAT Waves A - Properties, SHM

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1. Simple harmonic motion (SHM) is defined as motion where

• A. the velocity is proportional to the displacement, directed away from the centre of motion
• B. the velocity is proportional to the acceleration, directed towards the centre of motion
• C. the acceleration is proportional to the velocity, directed away from the centre of motion
• D. the acceleration is proportional to the displacement, directed towards the centre of motion
• E. the acceleration is proportional to the force applied, but in the opposite direction.

The graphs show a progressive (travelling) transverse wave at a particular point in time. Points P and Q on the wave are moving in a direction perpendicular to the wave. The wave is moving left to right in the diagram.

2. P and Q are out of phase by (in radians)

• A. 2π
• B. π
• C. 3π / 4
• D. π / 2
• E. π / 4

3. The subsequent motion of the two points will be:

• A. Q stays stationary, P moves up
• B. P moves up, Q moves down
• C. Q moves up, P moves down
• D. Both points move upwards
• E. Both points move downwards
4. In a sound wave regions of high pressure are compressions, and regions of low pressure are called
• A. depressions
• B. decompressions
• C. isobars
• D. expansions
• E. rarefactions
5. The wavelength of an ultra-violet wave is approximately
• A. 10-4m
• B. 10-6m
• C. 10-8m
• D. 10-10m
• D. 10-12m

A mass oscillates on a spring as shown, performing simple harmonic motion (SHM).

Oleg Alexandrov http://commons.wikimedia.org/

6. Which of these answers gives the points of maximum velocity and acceleration?

 Velocity maximum at ... Acceleration maximum at.. A the center the top B the top the center C the top the bottom D the center the center E the bottom the bottom

The graph below shows the displacement x of the mass on the spring shown above, at a time t.

7. What will be the phase difference between this graph and a graph showing the velocity of the mass?
• A) In phase
• B) π / 2 phase difference
• C) π / 4 phase difference
• D) π / 8 phase difference
• E) π phase difference
8. The frequency of this oscillation is
• A) 0.25 Hz
• B) 0.5 Hz
• C) 1 Hz
• D) 2 Hz
• E) 4 Hz

9. At the point where the mass is at the top of the oscillation, which of the following statements are true?

 I The system has maximum gravitational potential energy II The system has zero kinetic energy III The system has maximum elastic energy

• A) I only
• B) III only
• C) I and II only
• D) II and III only
• E) all 3 statements are true
10. The total energy of the system is
• A) maximum at the top of the oscillation
• B) maximum at the midpoint of the oscillation
• C) maximum at the bottom of the oscillation
• D) always zero
• E) always constant