If the radiant energy received from an electric bulb per second is $25 \ J/s$ and the velocity of electromagnetic waves is $c = 3 \times 10^8 \ m/s$,then the force exerted on the surface in one second is:

What is the force exerted on a surface having an area of $10\, cm^2$ due to the radiation of the Sun?

$A$ photon of wavelength $6630 \ \mathring{A}$ is incident on a totally reflecting surface. The momentum delivered by the photon is equal to

Light with an energy flux of $18 \; W/cm^2$ falls on a non-reflecting surface at normal incidence. If the surface has an area of $20 \; cm^2$,find the average force exerted on the surface during a $30$ minute time span.

If $2.5 \times 10^{-6} \ N$ average force is exerted by a light wave on a non-reflecting surface of $30 \ cm^{2}$ area during $40$ minutes of time span,the energy flux of light just before it falls on the surface is .................. $W/cm^{2}$. (Round off to the Nearest Integer) (Assume complete absorption and normal incidence conditions are there)

$A$ small mirror of mass $m$ is suspended by a massless thread of length $l$. Find the small angle through which the thread will be deflected when a short pulse of laser of energy $E$ falls normally on the mirror. ($c=$ speed of light in vacuum and $g=$ acceleration due to gravity)