JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
Given below are two statements Statement \(I\) : The electric force changes the speed of the charged particle and hence changes its kinetic energy: whereas the magnetic force does not change the kinetic energy of the charged particle Statement \(II\) : The electric force accelerates the positively charged particle perpendicular to the direction of electric field. The magnetic force accelerates the moving charged particle along the direction of magnetic field. In the light of the above statements, choose the most appropriate answer from the options given below
- A Both Statement \(I\) and Statement \(II\) are correct
- B Both Statement \(I\) and Statement \(II\) are incorrect
- C Statement \(I\) is correct but Statement \(II\) is incorrect
- D Statement \(I\) is incorrect but Statement \(II\) is correct
Answer & Solution
Correct Answer
(C) Statement \(I\) is correct but Statement \(II\) is incorrect
Step-by-step Solution
Detailed explanation
Electric field can change speed and kinetic energy but magnetic field can not change speed \(\triangle KE\). Because magnetic force is always \(\perp\) to velocity.
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