Question

A pulse is transmitted down a long string made of two pieces of different materials. If the wavelength of the pulse received at the end is longer than at the beginning, this implies that the speed of the pulse in the second part of the string is

Answer 1

Options

1. the same as in the first.

2.greater than in the first

3.less than in the first.

4.Unable to determine

Answer

The answer is 2. Greater than in the first

Explanation

The speed of a wave v is related to its wavelength λ by the formulav=f λ, where f is the frequency of the wave. The frequency will not change when the wave passes into a second medium, so

λ2>λ1

Fλ1>fλ2

Since f>0

And V2>v1