# GENERAL KNOWLEDGE

## GK

### PHYSICS

 Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
What is the rotational kinetic energy of the cylinder at t = 2 s?
 A 2.0J B 2.5J C 5.0J D It cannot be determined without knowing the radius
Explanation:

Detailed explanation-1: -The rotational kinetic energy is the kinetic energy of rotation of a rotating rigid body or system of particles, and is given by K=12I2 K = 1 2 I 2, where I is the moment of inertia, or “rotational mass” of the rigid body or system of particles.

Detailed explanation-2: -At time t = 0 the cylinder is at rest. At time t = 2 seconds its angular velocity is 1 radian per second.

Detailed explanation-3: -Its formula is: (KE)T=12(mv2) ( K E ) T = 1 2 ( m v 2 ) where (KE)T ( K E ) T is the translational kinetic energy, m is the mass of the object, and v is the translational/linear velocity of the object.

Detailed explanation-4: -Rotational energy also known as angular kinetic energy is defined as: The kinetic energy due to the rotation of an object and is part of its total kinetic energy. Rotational kinetic energy is directly proportional to the rotational inertia and the square of the magnitude of the angular velocity.

There is 1 question to complete.