1.A vibrating object completes 240 cycles in 15 s. What is its frequency, in hertz?

Question

240 Hz
16 Hz
0.0625 Hz
15 Hz

2.A standing wave is set up in a pool 24 m long which contains six loops. What is the wavelength?
8m
24m
48m
4m

3.A jet is flying at Mach 1.5. If the speed of sound in air is 320 m/s, what is the speed of the jet in m/s?
480 m/s
500 m/s
340 m/s
321.5 m/s

Answer 1

#1. 240/15
#2. depends on what a "loop" is. If you mean a half-period, then 24/3
#3. 320 * 1.5 m/s

Answer 2

123