The number of photons emitted per second from a $60 \ W$ light bulb is .......... . The wavelength of the photon is $660 \ nm$. $(h = 6.6 \times 10^{-34} \ J \cdot s)$

$A$ photon of wavelength $4400 \, \mathring{A}$ is passing through vacuum. The effective mass and momentum of the photon are respectively

$A$ laser produces a beam of light of frequency $5 \times 10^{14} \,Hz$ with an output power of $33 \,mW$. The average number of photons emitted by the laser per second is (Planck's constant $h = 6.6 \times 10^{-34} \,J \,s$)

The number of photons emitted by a $10\,W$ bulb in $10\,s,$ if the wavelength of light is $1000\,\mathring{A},$ is:

$A$ photodiode sensor is used to measure the output of a $300 W$ lamp kept $10 m$ away. The sensor has an opening of $2 cm$ in diameter. How many photons enter the sensor if the wavelength of the light is $660 nm$ and the exposure time is $100 ms$? (Assume that all the energy of the lamp is given off as light and $h = 6.6 \times 10^{-34} J s$)

If the wavelength of an $X-ray$ is $0.010 \ \mathring A$,what is its momentum?