The equation of motion of a body of mass 20 kg in SHM i

The equation of motion of a body of mass 20 kg in SHM i
| The equation of motion of a body of mass 20 kg in S.H.M. is y=0.04sin(100t+π4). Then 
i) Amplitude  is 0.04 m
ii) Frequency  is 15.92 Hz.
iii) Initial phase ϕ=π4 radians. 
iv) Vmax=4ms1.
v) amax=400ms2.
vi) Max. k.E =  160 J

A. 1,2 and 3 are correct

B. 1,3 and 4 are correct

C. All are correct

D. 1, 2 3 and 5 are correct

Please scroll down to see the correct answer and solution guide.

Right Answer is: C

SOLUTION

Compare the above equation with standard equation y=Asin(ωt+ϕ) 

i) Amplitude A = 0.04m
ii) Frequency ω2π=1002π=1006.28=15.92Hz. 
iii) Initial phase ϕ=π4 radians. 
iv) Vmax=ωA=100×0.04=4ms1.
v) amax=ω2A=1002×0.04=400ms2.
vi) Max. k.E = 12 m (Vmax)2=12×20×4×4=160J.