First slide

Photoelectric effect and study of photoelectric effect

Question

A silver ball of radius 4.8 cm is suspended by a thread in the vacuum chamber. UV light of wavelength 200 nm is incident on the ball for some times during which a total energy of 1 x 10^-7 J falls on the surface. Assuming on an average one out of 10³ photons incident is able to eject electron, The potential on sphere will be

Moderate

A

1V
B

2V
C

3V
D

Zero

Solution

$\begin{array}{l} n = \frac{E λ}{h c} = \frac{1 \times 10^{- 7} \times 200 \times 10^{- 9}}{6.6 \times 10^{- 34} \times 3 \times 10^{8}} = 1 \times 10^{11} \\ Number of electrons ejected \frac{10^{11}}{10^{3}} = 10^{8} \end{array}$
$v = \frac{k q}{r} = \frac{9 \times 10^{9} \times 10^{8} \times 1.6 \times 10^{- 19}}{4.8 \times 10^{- 2}} = 3 V$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App