POP QUIZ (CHAPTER 15-17)

In simple harmonic motion, the restoring force must be proportional to the

• velocity

• frequency

• amplitude

• displacement

A particle moves in simple harmonic motion according to the following equation: x=2cos (50 t) where x is in meters and t is in seconds. Its maximum speed (in m/s) is

• 100 sin (50t)

• 100 cos (50t)

• 100

• 200

The frequency of simple pendulum P is twice the frequency of simple pendulum Q. Which of the following statement is CORRECT?

• Pendulum Q is twice as long as P.

• Pendulum Q is twice as massive as P.

• Pendulum Q is quadrupled as long as P.

• Pendulum Q is quadrupled as massive as P.

Which of the following is a FALSE statement?

• Sound waves are longitudinal pressure waves.

• Sound can travel through a vacuum.

• Light travels very much faster than sound.

• The transverse waves on a vibrating string are different from sound waves.

The intensity of a point source at a distance d from the source is I. What is the intensity at a distance 2d from the source?

• 4 I

• 2 I

• 12I

• 14I

In a standing wave, the distance between adjacent nodes is

• 14λ

• 12λ

• λ

• 2λ

A wave on a string is reflected from a fixed end. The reflected wave, when compared to the incident wave, is

• inverted, same shape

• inverted, different shape

• non-inverted, same shape

• non-inverted, different shape

The fundamental frequency in a pipe closed at one end is 330 Hz. What is the frequency of the second resonance?

• 110 Hz

• 220 Hz

• 660 Hz

• 990 Hz

[Instruction for this question : Please show your solution on paper]

Abu and Ali are playing with a tin can telephone. Both of them are 14 m apart, the string connecting their tin cans has a linear mass density of 1.3 g/m and it is stretched with a tension of 9.0 N. Mus’ab decides to pluck the string.

How long does it take for the wave pulse to travel from Abu and Ali?

• 0.17 s

• 0.27 s

• 0.37 s

• 0.47 s

[Instruction for this question: Please show your solution on paper]

An organ pipe closed at one end has a length of 0.348 m. Calculate the fundamental frequency.

Given the speed of sound in air is 343 m/s                                    

• 246 Hz

• 346 Hz

• 343 Hz

• 443 Hz