Question

The displacement of a particle of mass 100 g executing SHM is given by the equation $y=0.2\cos (100t+\frac{\pi }{4})$metre. Its total energy is :

• A. 1 J
• B. 10 J
• C. 2 J
• D. 20 J

Answer 1

The correct option is D 20 J

Solution In SHM,

$y=0.2cos(100t+\frac{\pi }{4})$

A = 0.2m and w = 100 rad/s

we know,

Total energy = $\frac{1}{2}m(Aw{)}^2$

$TE=\frac{1}{2}\left(\frac{1}{10}\right)(0.2\times 100{)}^2$

$TE=\frac{(20{)}^2}{20}=20.J$

option -D is correct.