Mar 06,2021
Science Articles

# WHAT ARE SOME FORMULAS AND EXAMPLES OF ROTATIONAL MOTION?

Rotational motion is a kind of motion in which the body follows a curved path. For example, the wheel of the car or train is in constant rotational motion.

INTRODUCTION

Rotational motion is a kind of motion in which the body follows a curved path. For example, the wheel of the car or train is in constant rotational motion.

DIFFERENCES BETWEEN LINEAR AND ROTATIONAL MOTION

In a linear motion, a body follows straight paths. The attributes which define any linear motion are displacement, velocity, acceleration, momentum and force applied to move he body. Where as, attributes used to define any rotational motion are angular displacement, angular velocity and acceleration, angular momentum and torque. The formula for all of these is in parallel to formula of attributes in the linear motion.

SIMILARITY BETWEEN LINEAR AND ROTATIONAL MOTION

In linear motion we define, velocity as –

Velocity = displacement / time

In rotational motion we define angular velocity (rate of change of angle with respect to time) as–

Angular velocity (w) = Dq / Dt

where Dq is the angular displacement and Dt is the time taken to make this displacement.

In linear motion we define we define force as,

F = Dp / Dt = ma

where  Dp is the change in linear momentum in time Dt, m is the mass of the body and a is the acceleration of the body.

In rotational motion we define torque as the rotational analogue.

t = DL / Dt = I * a

where L is the angular momentum analogous to linear momentum p, I is moment of inertia which is analogous to mass of the body m, a is the angular acceleration which is analogous to linear acceleration a.