Question

In a television picture tube the electrons are accelerated from rest through a potential difference V. Just before an electron strikes the screen, its de Broglie wavelength is 8.00 10-12 m. What is the potential difference

Answer 1

V = 23515.53volt

Step-by-step explanation:

wavelength λ= 1.1 x 10 -11 m

We know λ= h /√ [2mVq]

Where h = Plancks constant

= 6.625 x 10 -34 J s

m = mass of electron

= 9.11 x 10 -31 kg

q = charge of eectron

=1.6 x 10 -19 C

From above potential difference V = ( 1/2mq) (h /λ)²

`V = ((1)/(2mq) )((h)/(\lambda) )^2`

`V = ((1)/(2*9.11*10^(-31)*1.6*10^(-19)) )((6.625*10^(-34))/(8*10^(-12)) )^2`

`V = ((1)/(2.9152*10^(-49)) )(8.28*10^(-23) )^2\\\\V= (3.43*10^(48))(6.85*10^(-45))\\\\V = 23515.53volt`

V = 23515.53volt