$A$ 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

Light having an energy flux of $40 \ Wcm^{-2}$ falls on a non-reflecting surface at normal incidence. If the surface has an area of $20 \ cm^2$,the total momentum delivered (for complete absorption) during $10 \ min$ is:

The force on a hemisphere of radius $1\, cm$ if a parallel beam of monochromatic light of wavelength $500\, nm$ falls on it with an intensity of $0.5\, W/cm^2$,striking the curved surface in a direction which is perpendicular to the flat face of the hemisphere is (assume the collisions to be perfectly inelastic).

$A$ pulse of light of duration $100 \ ns$ is absorbed completely by a small object initially at rest. The power of the pulse is $30 \ mW$ and the speed of light is $3 \times 10^8 \ m/s$. The final momentum of the object is:

Radiations of intensity $0.5 \ Wm^{-2}$ are striking a metal plate. The pressure exerted on the plate is:

Find the compression in the spring with spring constant $K = 5 \ N/m$ which is attached to a metal plate of area $50 \ m^2$. Light of intensity $I = 40 \ MW/m^2$ is incident at an angle of $60^o$ on the metal plate,and the coefficient of reflection is $\rho = 0.5$ for the plate. (in $m$)