Solveeit Logo
Login

Question

Question: A particle of mass \(10^{- 3}\)kg and charge \(5\mu C\)is thrown at a speed of \(20ms^{- 1}\)against...

A particle of mass 10−310^{- 3}kg and charge 5μC5\mu Cis thrown at a speed of 20ms−120ms^{- 1}against a uniform electric field of strength 2×105NC−1.2 \times 10^{5}NC^{- 1}. The distance travel by particle before coming to rest is

A

0.1 s

B

0.2 s

C

0.3 s

D

0.4 s

Answer

0.2 s

Explanation

Solution

: F=qE=5×10−6×2×105=1NF = qE = 5 \times 10^{- 6} \times 2 \times 10^{5} = 1N

Since, the particle is thrown against the field

∴a=−F/m=−110−3=−103ms−2\therefore a = - F/m = - \frac{1}{10^{- 3}} = - 10^{3}ms^{- 2}

As v2−u2=2asv^{2} - u^{2} = 2as

∴02−(20)2=2×(−103)×s\therefore 0^{2} - (20)^{2} = 2 \times ( - 10^{3}) \times s

Or s = 0.2 m