Assertion: Velocity and acceleration of a particle in circular motion at some instant are:
`v=(2hat(i))ms^(-1)` and `a=(-hat(i)+2hat(j))ms^(-2)` , then radius of circle is `2m` .
Reason: Speed of particle is decreasing at a rate of `1ms^(-2)` .

Options

A. If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. If Assertion is true, true but the Reason is false.
D. If Assertion is false but the Reason is true.

Answer

B

Explanation

Component of acceleration perpendicular to velocity is centripetal acceleration.
:. `a_(c)=(v^(2))/(R)` or `R=(v^(2))/(a_(c))=((2)^(2))/(2)=2m`