Home
Class 12
PHYSICS
Light with an energy flux of 20 "W/cm"^(...

Light with an energy flux of `20 "W/cm"^(2)` falls on a non-reflecting surface at normal incidence. If the surface has an area of `"30 cm"^(2)`, the total momentum delivered (for complete absorption) during 30 minutes is

A

`36 xx 10^(-5) kg-m//s`

B

`36 xx 10^(-4) kg-m//s`

C

`108 xx 10^(4) kg-m//s`

D

`1.08 xx 10^(7) kg-m//s`

Text Solution

Verified by Experts

The correct Answer is:
B
Given energy flux `phi =20W//cm^(2)`
Area `A = 30cm^(2)`
Time , `t= 30min =30 xx 60s`
Now , total energy falling on the surface in time is `u=phiAt =20 xx 30 xx (30 xx 60)J`
Momentum of the incident light `=U/C`
`=(20 xx 30 xx (30 xx 60))/(3xx 10^(8)) rArr = 36 xx 10^(-4) kg-ms^(-1)`
Momentun of the reflected light =0
`:.` Momentum delivered to the suface
`=36 xx 10^(-4) -0 =36 xx 10^(-4) kg-ms^(-1)`
Promotional Banner

Topper's Solved these Questions

  • ELECTROMAGNETIC WAVES

    NCERT EXEMPLAR ENGLISH|Exercise MCQ (MORE THAN ONE OPTIONS )|4 Videos

  • ELECTROMAGNETIC WAVES

    NCERT EXEMPLAR ENGLISH|Exercise VERY SHORT ANSWER|7 Videos

  • ELECTROMAGNETIC INDUCTION

    NCERT EXEMPLAR ENGLISH|Exercise Long|11 Videos

  • ELECTROSTATIC POTENTIAL AND CAPACITANCE

    NCERT EXEMPLAR ENGLISH|Exercise Long Answer Type Question|10 Videos

Similar Questions

Explore conceptually related problems

Light with an energy flux 20 W//cm^2 falls on a non-reflecting surface at normal incidence. If the surface has an area of 30 cm^2 . the total momentum delivered ( for complete absorption)during 30 minutes is

Light with an energy flux 20 W//cm^2 falls on a non-reflecting surface at normal incidence. If the surface has an area of 30 cm^2 . the total momentum delivered ( for complete absorption)during 30 minutes is

Light with an energy flux 20 W//cm^2 falls on a non-reflecting surface at normal incidence. If the surface has an area of 30 cm^2 . the total momentum delivered ( for complete absorption)during 30 minutes is

Light with an energy flux of 18W//cm^(2) falls on a non-reflecting surface at normal incidence. The pressure exerted on the surface is

Light with an energy flux of 18 W//cm^2 falls on a non-reflecting surface at normal incidence. If the surface has an area of 20 cm^2 , find the average force exerted on the surface during a 30 minute time span.

Light with an energy flux of 18 W//cm^2 falls on a non-reflecting surface at normal incidence. If the surface has an area of 20 cm^2 , find the average force exerted on the surface during a 30 minute time span.

Light with an enargy flux of 25xx10^(4) Wm^(-2) falls on a perfectly reflecting surface at normal incidence. If the surface area is 15 cm^(2) , the average force exerted on the surface is

Light with an energy flux of 18 W cm^(-2) falls on a non-reflecting surface at normal incidence. If the surface at normal incidence. If the surface has an area of 20 cm^(2) , find the average force exerted on the surface during a span of 30 min.

Light with an average flux of 20 W/(cm)^2 falls on a non-reflecting surface at normal incidence having surface area 20 cm^2 . The energy received by the surface during time span of 1 minute is:

Light is incident normally on a completely absorbing surface with an energy flux of 25 Wcm^(-2) If the surface has an area of 25 cm^(2) the momentum transferred to the surface in 40 min time duration will be: