Modern Physics 7 Question 4
4. Light is incident normally on a completely absorbing surface with an energy flux of . If the surface has an area of , the momentum transferred to the surface in time duration will be
(a)
(b)
(c)
(d)
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Solution:
- Radiation pressure over an absorbing surface is,
where, =intensity or energy flux
and
If
If force
Here,
So, momentum transferred to the surface,