List of top Questions asked in JEE Advanced- 1994

During paddling of a bicycle, the force of friction exerted by the ground on the two wheels is such that it acts

Two bodies A and B have thermal emissivities of 0.01 and 0.81 respectively. The outer surface areas of the two bodies are the same. The two bodies emit total radiant power at the same rate. The wavelength $\lambda_B$ corresponding to maximum spectral radiancy in the radiation from B shifted from _the wavelength corresponding to maximum spectral radiancy in the radiation from A, by 1.00 pm. If the temperature of A is 5802 K.

A particle of mass $m$ is moving in a circular path of constant radius $r$ such that centripetal acceleration $a_{c}$ varying with time is $a_{c}=k^{2}\, r \,t^{2}$ where $k$ is a constant. What is the power delivered to the particle by the force acting on it?