An electromagnetic wave of intensity $1400 \, W/m^2$ falls on a metal surface of area $1.5 \, m^2$ and is completely absorbed by it. Find the force exerted by the beam.

$A$ bulb of power $660 \,W$ radiates uniformly in all directions. The pressure exerted by the radiation on the surface at a distance of $5 \,m$ is

Electromagnetic radiation of intensity $0.6 \ W/m^2$ is falling on a black surface. The radiation pressure on the surface is

$A$ beam of white light is incident normally on a plane surface absorbing $70 \%$ of the light and reflecting the rest. If the incident beam carries $10 \ W$ of power,the force exerted by it on the surface is

$A$ light beam of intensity $20 \,W/cm^2$ is incident normally on a perfectly reflecting surface of sides $25 \,cm \times 15 \,cm$. The momentum imparted to the surface by the light per second is

Light falls on a non-reflecting surface normally. If the average force exerted on a surface with area $15 \text{ cm}^2$ during a $20 \text{ minute}$ time interval is $10^{-6} \text{ N}$,then the energy flux (intensity) of light is (Velocity of light $= 3 \times 10^8 \text{ ms}^{-1}$)