The energy of a quantum of frequency $10^{15} \ Hz$ and $h = 6.6 \times 10^{-34} \ J \cdot s$ will be:

$A$ $60 \,W$ source emits monochromatic light of wavelength $662.5 \,nm$. The number of photons emitted per second is

What is the unit of energy in atomic and nuclear physics? Define it.

Calculate the number of photons entering the eye of a duck per second,corresponding to the minimum intensity of white light $(\sim 10^{-10} \ W/m^2)$. Take the area of the duck's eye as $0.4 \ cm^2$ and the average frequency of white light as $6 \times 10^{14} \ Hz$.

If $h$ is Planck's constant,the momentum of a photon with a wavelength of $0.01 \ \mathring A$ is .........

$A$ photon of frequency $v$ has a momentum associated with it. If the speed of light is $c$,then the momentum is .......