Question

the time period of oscillation of a particle that execute SHM is 1.2 second that time starting from extreme position its velocity will be half of its velocity at mean position

Answer 1

On starting from mean position, the equation for displacement is x=Asin(wt). However, starting from the right extreme, the equation is x=Acos(wt). This is because the angle changes by π/2 as we go from mean to extreme. If we see SHM as a form of circular motion, sin(π/2+x)=cos (x). Hence, the time taken changes in the two cases