A loudspeaker diaphragm is producing a sound for 4.6 s by moving back and forth in simple harmonic motion. The angular frequency of the motion is 2.57 x 104 rad/s. How many times does the diaphragm move back and forth

Number of times the  diaphragm move back and forth is  5.59×10^4

Explanation:

Given data,

ω=4.6 s

we have the formula

f=ω/2π

The number of times the diaphragm moves back and forth in 4.6 s is

Number of times= ft

Number of times= ft

                           =(ω/2π) t

                          =(7.54×10^4 rad/sec)(4.6 s)/2π

Number of time=5.59×10^4

Number of times the  diaphragm move back and forth is  5.59×10^4

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.