Question

Calculate the speed of an electron that has fallen through a potential difference of

(a) 125 volts and

(b) 125 megavolts.

Answer 1

Step-by-step explanation:

We need to find the speed of an electron that has fallen through a potential difference of 125 volts. It can be calculated using the De-broglie hypothesis as :

(a) V = 125 volts

`(1)/(2)mv^2=qV`

Where

v = speed of electron

V is potential difference

`v=\sqrt{(2qV)/(m)}`

`v=\sqrt{(2* 1.6* 10^(-19)* 125\ V)/(9.1* 10^(-31))}`

v = 6629935.44 m/s

`v=6.62* 10^6\ m/s`

(b) V = 125 megavolts

`V=1.25* 10^8\ V`

`v=\sqrt{(2qV)/(m)}`

`v=\sqrt{(2* 1.6* 10^(-19)* 1.25* 10^8\ V)/(9.1* 10^(-31))}`

`v=6.62* 10^9\ m/s`

Hence, this is the required solution.