Question

An electron is accelerated by a potential difference of 12000 volts. It then enters a uniform magnetic field of applied perpendicular to the path of electron. Find the radius of path. Given mass of electron and charge on electron $= 1.6 \times 10 ^ { - 19 } C$

• A. 36.7 m
• B. 36.7 cm
• C. 3.67 m
• D. 3.67 cm

Answer 1

Answer: (B)

36.7 cm

Answer 2

$r = \frac { \sqrt { 2 m K } } { q B } = \frac { 1 } { B } \sqrt { \frac { 2 m V } { q } }$

$= \frac { 1 } { 10 ^ { - 3 } } \sqrt { \frac { 2 \times 9 \times 10 ^ { - 31 } \times 12000 } { 1.6 \times 10 ^ { - 19 } } }$=0.367 m = 36.7 cm