JEE MainPhysicsMagneticsMCQ+4 / −1
A particle of mass m and charge q is in an electric and magnetic field given by The charged particle is shifted from he origin to the point P(x = 1; y = 1) along a straight path. The magnitude of the total work done is :
- A(2.5) q
- B(0.35) q
- C(0.15) q
- D5 q
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Correct answer: D
-
Given fields
The particle is moved from the origin to point along a straight line.
-
Work done by magnetic field
Magnetic force is always perpendicular to velocity:
Hence,
So only the electric field does work.
-
Work done by electric field
Electric force:
Displacement from origin to is
Therefore work done:
-
Magnitude of total work done
-
Option check
- A: ❌
- B: ❌
- C: ❌
- D: ✅
Therefore, the correct answer is D.
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