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

If $P$ represents radiation pressure,$c$ represents the speed of light,and $Q$ represents radiation energy striking a unit area per second,then non-zero integers $x, y,$ and $z$ such that $P^x Q^y c^z$ is dimensionless are:

$A$ light bulb of power $100 \ W$ is placed at the centre of a hollow sphere of radius $10 \ cm$. If $66\%$ of the energy is converted into light,then the pressure exerted by the light on the surface of the sphere will be (Assume the surface of the sphere to be perfectly absorbing).

$A$ parallel beam of monochromatic light of frequency $\nu$ is incident on a surface. The intensity of the beam is $I$ and the area of the surface is $A$. Find the force exerted by the light beam on the surface if it is perfectly reflecting and the light beam is incident at an angle of incidence $\theta$. (The speed of light is denoted as $c$.)

Average force exerted on a non-reflecting surface at normal incidence is $2.4 \times 10^{-4} \,N$. If $360 \,W/cm^2$ is the light energy flux during a span of $1$ hour $30$ minutes,then the area of the surface is: (in $\,m^2$)

Light with an energy flux of $25 \times 10^4 \, W/m^2$ falls on a perfectly reflecting surface at normal incidence. If the surface area is $15 \, cm^2$,the average force exerted on the surface is: