A laser used to weld detached retains emits light with a wavelength $652$ nm in pulses that are of $20 m s$ duration. The average power during each pulse is $0.6 W$ . The energy in each pulse and in a single photon are :
$7.5 \times 10^{15} e V, 2.7 e V$
$6.5 \times 10^{16} e V, 2.9 e V$
$6.5 \times 10^{16} e V, 2.7 e V$
$7.5 \times 10^{16} e V, 1.9 e V$

Question

A laser used to weld detached retains emits light with a wavelength $652$ nm in pulses that are of $20 m s$ duration. The average power during each pulse is $0.6 W$ . The energy in each pulse and in a single photon are :
$7.5 \times 10^{15} e V, 2.7 e V$
$6.5 \times 10^{16} e V, 2.9 e V$
$6.5 \times 10^{16} e V, 2.7 e V$
$7.5 \times 10^{16} e V, 1.9 e V$

Toppr Admin · Accepted Answer

Energy of photon -hc-x3BB-1240eV-x2212-nm652nm-xA0-xA0-xA0-xA0-hc-1240eV-x2212-nm-xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -xA0- -1-9eV

A laser used to weld detached retains emits light with a wavelength 652 nm in pulses that are of 20ms duration. The average power during each pulse is 0.6W. The energy in each pulse and in a single photon are :7.5×1015eV,2.7eV6.5×1016eV,2.9eV6.5×1016eV,2.7eV7.5×1016eV,1.9eV

Energy of photon =hcλ=1240eV−nm652nm (hc=1240eV−nm) =1.9eV

Energy of photon $= \frac{h c}{λ}$ $= \frac{1240 e V - n m}{652 n m} (h c = 1240 e V - n m)$

$= 1.9 e V$