Question

The period of a wave is 20 ms (milliseconds) and its wavelength is 4 cm. Calculate:

Answer 1

Answer:

A. 50 Hz

B. 2 m/s

Explanation:

We'll begin by converting 20 ms to s. This can be obtained as follow:

1000 ms = 1 s

Therefore,

20 ms = 20 ms × 1 s / 1000 ms

20 ms = 0.02 s

Next, we shall convert the value of the wavelength (i.e 4cm) to m. This can be obtained as follow:

100 cm = 1 m

Therefore,

4 cm = 4 cm × 1 m / 100 cm

4 cm = 0.04 m

A. Determination of the frequency.

Period (T) = 0.02 s

Frequency (f) =?

f = 1 / T

f = 1 / 0.02

f = 50 Hz

Therefore, the frequency of the wave is 50 Hz

B. Determination of the velocity.

Wavelength (λ) = 0.04 m

Frequency (f) = 50 Hz

Velocity (v) =?

v = λf

V = 0.04 × 50

v = 2 m/s

Therefore, the velocity of the wave is 2 m/s