Question

A disc rotates about its axis with a uniform acceleration of 10 rad s2. The radial and tangential accelerations of a particle at a distance 2 cm from the axis, two seconds after the disc starts rotating are

Answer 1

Given in the question

Angular accelaration α = 4 rad/s²

Distance, r = 1 cm = 0.01 m

Now for finding the tangential acceleration we know,

Tangential acceleration a is eqaul to

a = rα

a= 0.01 m x 4 rad/s²

a=0.04 m/s²

a= 4 cm/s².

For finding the value of radial acceleration

First we have to know ω on the end of first second disc.

ω= 0 + αt

ω=4 x 1

ω =4 rad/s

Now,

Radial acceleation = ω²r

= 4² x 0.01

=0.16 m/s²

= 16 cm/s².