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An electron and a proton are moving und...

An electron and a proton are moving under the influence of mutual forces . In calculating the change in the kinetic energy of the system during motion , one ignores the magnetic force of one on another . This is , because

A

the two magnetic forces are equal and opposite ,so they produce no net effect

B

the magnetic forces do not work on each particle

C

the magnetic forces do equal and opposite (but non -zero) work on each particle .

D

the magnetic forces are necessarily negligible .

Text Solution

Verified by Experts

The correct Answer is:
B
When electron and proton are moving under influence of their mutual forces , the magnetic forces are perpendicular to tem hence work done by these forces is zero .
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