Trapping of Electromagnetic Radiations – Rankers Physics

Properties of EM Waves: Practice Problem & Solution

Assertion (A): Electromagnetic radiations like UV, visible and IR coming from Sun towards earth's surface can't be trapped by earth's magnetic field where as cosmic rays coming towards earth's surface are trapped by the magnetic field of earth. Reason (R): Electromagnetic wave doesn't contain any live charge where the cosmic rays is a huge storage of charged particle.  
Both (A) \(&\) (R) are true and the (R) is the correct explanation of the (A)
Both (A) \(&\) (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Properties of EM Waves. Understanding the underlying formula is key to arriving at the correct answer below:

Electromagnetic waves consist of photons and carry no charge, hence they are unaffected by magnetic fields. Cosmic rays are composed of charged particles, which experience a Lorentz force in the Earth's magnetic field, causing them to be trapped or deflected. Thus, R correctly explains A.

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