Calculate for potential energy

Asmall grinding wheel has a moment of inertia of 4.0×10−5 kg⋅m2 . what net torque must be applied to the wheel for its angular acceleration to be 150 rad/s2 ?

Aspecified volume of space contains an electric field for which the magnitude is given by e=e0cos(ωt). suppose that e0 = 20 v/m and ω = 1.0 × 107 s−1. part a what is the maximum displacement current through a 0.80 m2 cross-sectional area of this volume? express your answer with the appropriate units. idisp,max i d i s p , m a x = nothing nothing request answer part b how would this area have to be oriented relative to the electric field to get this maximum displacement current?

Acar traveling at a constant speed of 22.0 m/s passes a trooper hidden behind a billboard. one second after the speeding car passes the billboard, the trooper sets off in chase with a constant acceleration of 3.50 m/s2. how long does it take the trooper to overtake the speeding car? solve this problem by a graphical method. on the same graph, plot position versus time for the car and the trooper.