Question

An electron moving with a velocity of 5 × 104m s-1 enters into a uniform electric field and acquires a uniform acceleration of 104 m s–2 in the direction of its initial motion. (i) Calculate the time in which the electron would acquire a velocity double of its initial velocity.
(ii) How much distance the electron would cover in this time?

Answer 1

Given initial velocity, u = 5 × 104 m s-1  and acceleration, a = 104 m s–2  (i) final velocity = v = 2 u = 2 × 5 ×104 m s–1 =10 × 104 m s–1  To find t,      use  v  =  at                      or t = u - u / a (ii)           Using s = ut + 1/ 2 at 2  = (5 ×104) × 5 + 1/ 2 (10 ) × (5) 2 = 25 ×104 + 25 /2 ×104 = 37.5×104 m

Answer 2

Answer:

An electron moving with a velocity of 5 × 104 m s-1 enters into a uniform

electric field and acquires a uniform acceleration of 104 m s–2 in the direction

of its initial motion.

(i) Calculate the time in which the electron would acquire a velocity double

of its initial velocity.

(ii) How much distance the electron would cover in this time?