Question

The velocity of an electron having K.E 1.5MeV is​

Answer 1

Explanation:

we have observed speed of electron is '5.988 * 10^8 m/s ' having kinetic energy 1.02MeV!! But terribly it is about two times the speed of light (3 * 10^8 m/s) . ... But terribly it is about two times the speed of light (3 * 10^8 m/s) .

Answer 2

Answer:

Option D → 7.2×10⁸m/s

Explanation:

K.E→ 1.5MeV → 1500000eV→ 2.4×10-¹³J

m→9.1×10-³¹kg

v=?

K.E=½ mv²

v²=2K.E/m

v²=2 × 2.4×10-¹³ / 9.1×10-³¹

v²=4.8×10-¹³ × 10+³¹ / 9.1

v²=0.52×10¹⁸

v=√52×10¹⁶

v=7.2×10⁸ m/s

Hence, Option D is 100% Right ✓.