Physics
Grade-9
Easy
Question
The periodic time of a body executing simple harmonic motion is 3 sec. After how many intervals from time t = 0, its displacement will be half of its amplitude:
-
sec -
sec
sec
sec
Hint:
The equation for SHM is given by,
y=Asinωt and ω=2πf=2π/T
The correct answer is:
sec
Given that, time period T=3seconds.
The equation for SHM is given by,
y=Asinωt and ω=2πf=2π/T
Let after time t=t, the displacement is half its amplitude,
A/2=Asin(2πt/3)
sin(π/6)=sin(2πt/3)
or, t=1/4 sec is our required answer.
or, t=1/4 sec is our required answer.
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