so, B was kinda wrong and C was the answer even though there are expert verified answers, why was it C?

Amachinist turns the power on to a grinding wheel, at rest, at time t = 0 s. the wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 96 rad/s. the wheel is run at that angular velocity for 40 s and then power is shut off. the wheel slows down uniformly at 1.5 rad/s2 until the wheel stops. in this situation, the time interval of deceleration is closest to:

Acoil suspended freely, points in some direction when no current is passed through it . can you tell what will happen when a current is passed though it?

The doctor lands his tardis on a planet whose radius is 1.2x10^7m the acceleration due to gravity is 18m/s^2. what is the mass of the planet