Physics Answers

Sound travels through air at a speed of 342 m/s at room temperature. To the nearest tenth of a meter, what is the wavelength of a sound wave with a frequency of 285 Hz?

A wave travelling along a string is describe by y(x,t) = 0.35sin(2.75t – 72.5x).

Determine

i. The velocity with which the wave moves along the string

(2 marks)

ii. The displacement of a particle located at x = 21.5 cm and t = 15.5 sec.

(3 marks)

The displacement of an object executing simple harmonic oscillations is given by:

x = 0.02 sin 2π ( t + 0.01 ) m

Determine (a) amplitude of the oscillatory motion, (b) time period of oscillation , (c) maximum velocity, (d) maximum acceleration, and (e) initial displacement of the object.

A car approaches a stop sign going 5 m/s before it comes to a stop. If it does this in 4 seconds, what was its acceleration?

A capacitor has a charge of 9 microcoulomb when connected with a 12 V battery. Determine the capacitance.

What is the charge stored when the voltage across a 25 milliard capacitor is 9 V?

What is the capacitance of a capacitor that stores 50 picocoulomb of charge when connected to a 4 V battery?

How much charge flows from a 12.0 V battery when it is connected to a 9.00 microfarad capacitor?

A sphere has a potential difference between it and the earth of 5 V when charged with 14 nanocoulomb. What is the capacitance?

For a certain sinusoidal wave of intensity I, the amplitude of the magnetic field is B. What

would be the amplitude (in terms of B) in a similar wave of twice the intensity?