Question

Which of the following have highest specific charge(a) Positron(b) Proton(c) He(d) None of these

Answer 1

proton has the highest specific charge

Answer 2

Answer:

(a) Positron

Explanation:

The specific charge is equal to the ratio of charge to mass. If charge is q and mass m then the ratio of the charge (q) to mass (m) is known as the specific charge.

For positron, me =9.1×10−31kg and e=1.6×10−19C

Thus, e/m = 1.6×10−19/ 9.1×10−31

= 1.75×10`11Ckg−1

For proton, mp =1.67×10−27kg and e=1.6×10−19C  

Thus, e/m=1.6×10−19/1.67×10−27

= 9.58×107Ckg−1

For Helium, mHe =6.6×10−27kg and He=2×1.6×10−19C

= e/m= 2×1.6×10−19/6.6×10−27

= 4.84×107Ckg−1

Thus, Positron has the highest specific charge.