Help with physics please?

Question

If a wave has a speed of 362 m/s and a period of 4.17 ms, its wavelength is closest to:

1.51 m

86,800 m

1510 m

0.0115 m

86.8 m

Answer 1

this question is to test two things off you. (1) whether you know

wavelength = speed X period

(2) how you can perform approximate calculations to get a sense of magnitude.

The quick calculation you need to work out is

362 m/s times 1 ms gives 0.362 m

and 0.362 m times 4.17 is between 1.2 and 1.6 m (namely 0.3x4 and 0.4x4).

so the answer is obviously 1.51 m. All the other answers differ by orders of magnitude.

Answer 2

1.51 m