Question

the potential difference between the electron gun and the TV screen is 2.5 kilo volts how much electron volt of energy does an electron lose on striking the screen​

Answer 1

Answer ⇒ Heat lost after striking =  4 × 10⁻¹⁶ J

Explanation ⇒

When the electron will be moving it has only kinetic energy. Now, when it hits the screen, its kinetic energy will be converted into heat and that heat appears out.

Given,

Potential of the Electron gun = 2.5 kV = 2500 V.

Also, Charge on electron (e) = 1.6 × 10⁻¹⁹ C.

Using the formula,

 Kinetic Energy = eV

∴ K.E. = 1.6 × 10⁻¹⁹ × 2500

∴ K.E = 4000 × 10⁻¹⁹

∴ K.E. = 4 × 10⁻¹⁶ J.

∴ Heat lost after striking =  4 × 10⁻¹⁶ J

Hope it helps.