Question

When needed, use 340 m/s for the speed of sound and 3.00 x 10⁸ m/s for the speed of light.

A hiker determines the length of a lake by listening for the echo of her shout reflected by a cliff at the far end of the lake. She hears the echo 2.20 s after shouting. How long is the lake?

Question 27 options:

	270 m
	374 m
	748 m
	170 m

View hint for Question 27

Question 28 (1 point)

Calculate the difference in the wavelengths in air for sounds in the maximum range of human hearing, 20 Hz to 20,000 Hz.

Question 28 options:

	48 m
	1.70 m
	0.270 m
	17 m

Answer 1

2 Solutum: - Sound speed of 340m/ ON 27 stine js 2.208 dl de lake depth 1 total de farce travelled by sound 2d 2 de ext - de ext - 340m/ x 2.200 2 2 374 m option 2 is correct O No 28 for 200 frequency f= 2042 wovelength 1 - 340 co. - 17m 20 m & for f= 200002 Hom/ s 01017 m 20000HE difference in wavelength d= -d=17 m - 0.01fm 17 m