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Assertion : The relative velocity of tw...

Assertion : The relative velocity of two photons travelling in opposite directions is C.
Reason : The rest mass of a photon is zero .

A

If both the assertion and reason are true statement and reason is correct explanation of the assertion .

B

If both the assertion and reason are true statement but reason is not a correct explanation of the assertion .

C

If the assertion is true but the reason is a false statement.

D

If both assertion and reason are false statements.

Text Solution

Verified by Experts

The correct Answer is:
B
Very high velocities can not be added directly as in classical mechanics because this would lead to a violatio of the postulates of relatively . Such velocities are added in accordance with Lorentz transformations . It can be proved that any velocity added to the velocity of light gives velocity of light .
Relativistic mass of photon -
The relativistic momentum of photon is `p=(m_(0)V)/(sqrt(1-((v^(2))/(c^(2))))`
But `p=(h)/(lambda)`
` :. (h)/( lambda)=(m_(0)V)/(sqrt(1-((v^(2))/(c^(2))))`
`m_(0)=(h)/(v lambda)sqrt(1-((v^(2))/(c^(2)))`
For a photon v=c , then , `m_(0)=0`
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