In the circuit shown below, the AC source has voltage V = 20cos(ω t)V with ω = 2000rad/s. The amplitude of the current will be nearly
A particle is moving in a straight line. The variation of position $ x $ as a function of time $ t $ is given as: $ x = t^3 - 6t^2 + 20t + 15 $. The velocity of the body when its acceleration becomes zero is: