Home
Class 12
PHYSICS
A sphere of radius 1.00 cm is placed in ...

A sphere of radius 1.00 cm is placed in the path of a parallel beam of light of large aperture. The intensity of the light is 0.50 W `cm^-2`. If the sphere completely absorbs the radiation falling on it, find the force exerted by the light beam on the sphere.

Text Solution

Verified by Experts

If a perfectly reflecting solid sphere of radius 'r' is kept in the path of a parallel beam of light of large aperture if intensity is l ,
` Force = pi r^(2)l/ c `
`l = 0.5 W / m^(2)`
`r = 1cm, c = 3 xx 10^(8) m / s `
`Force = pi xx (1) xx 0.5 / 3 xx10^(8) `
`= 3.14 xx 0.5 / 3 xx 10^(8)`
` 0.523 xx 10^(-8)`
` = 5.2 xx 10^(-9) N.
Promotional Banner

Topper's Solved these Questions

  • PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY

    HC VERMA|Exercise Exercise|2 Videos

  • PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY

    HC VERMA|Exercise Objective 2|7 Videos

  • PERMANENT MAGNETS

    HC VERMA|Exercise Exercises|25 Videos

  • PHOTOMETRY

    HC VERMA|Exercise Exercises|16 Videos

Similar Questions

Explore conceptually related problems

A concave lens is placed in the path of a uniform parallel of beam of light falling on a screen as shown . Then

A 100W sodium lamp radiates energy uniformly in all directions. The lamp is located at the centre of a large sphere that absorbs all the sodium light which is incident on it. The wavelength of the sodium light is 589 nm. (a) What is the energy per photon associated with the sodium light? (b) At what rate are the photons delivered to the sphere?

A 100 W sodium lamp radiates energy uniformly in all directions .The lamp located at the centre of a large sphere the absorbs all the sodium light which is incident on it.The wavelength of the sodium light 589 nm.(a) what is the energy per photo assosciated with the sodium light? (b)At what rate are the photons delivered to the sphere.

In the figure shown a converging lens and a diverging lens of focal lengths 20cm and -5cm respectively are separated by a distance such that a paralle beam of light of intensity 100 watt//m^(2) incident on the converging lens comes out as parallel beam from the diverging lens. Find the intensity of the outgoing beam in watt//m^(2)

An accelration produces a narrow beam of protons, each having an initial speed of v_(0) . The beam is directed towards an initially uncharges distant metal sphere of radius R and centered at point O. The initial path of the beam is parallel to the axis of the sphere at a distance of (R//2) from the axis, as indicated in the diagram. The protons in the beam that collide with the sphere will cause it to becomes charged. The subsequentpotential field at the accelerator due to the sphere can be neglected. The angular momentum of a particle is defined in a similar way to the moment of a force. It is defined as the moment of its linear momentum, linear replacing the force. We may assume the angular momentum of a proton about point O to be conserved. Assume the mass of the proton as m_(P) and the charge on it as e. Given that the potential of the sphere increases with time and eventually reaches a constant velue. One the potential of the sphere has reached its final, constant value, the minimum speed v of a proton along its trajectory path is given by

An accelration produces a narrow beam of protons, each having an initial speed of v_(0) . The beam is directed towards an initially uncharges distant metal sphere of radius R and centered at point O. The initial path of the beam is parallel to the axis of the sphere at a distance of (R//2) from the axis, as indicated in the diagram. The protons in the beam that collide with the sphere will cause it to becomes charged. The subsequentpotential field at the accelerator due to the sphere can be neglected. The angular momentum of a particle is defined in a similar way to the moment of a force. It is defined as the moment of its linear momentum, linear replacing the force. We may assume the angular momentum of a proton about point O to be conserved. Assume the mass of the proton as m_(P) and the charge on it as e. Given that the potential of the sphere increases with time and eventually reaches a constant velue. If the initial kinetic energy of a proton is 2.56 ke V , then the final potential of the sphere is

An accelration produces a narrow beam of protons, each having an initial speed of v_(0) . The beam is directed towards an initially uncharges distant metal sphere of radius R and centered at point O. The initial path of the beam is parallel to the axis of the sphere at a distance of (R//2) from the axis, as indicated in the diagram. The protons in the beam that collide with the sphere will cause it to becomes charged. The subsequentpotential field at the accelerator due to the sphere can be neglected. The angular momentum of a particle is defined in a similar way to the moment of a force. It is defined as the moment of its linear momentum, linear replacing the force. We may assume the angular momentum of a proton about point O to be conserved. Assume the mass of the proton as m_(P) and the charge on it as e. Given that the potential of the sphere increases with time and eventually reaches a constant velue. The limiting electric potential of the sphere is

An accelration produces a narrow beam of protons, each having an initial speed of v_(0) . The beam is directed towards an initially uncharges distant metal sphere of radius R and centered at point O. The initial path of the beam is parallel to the axis of the sphere at a distance of (R//2) from the axis, as indicated in the diagram. The protons in the beam that collide with the sphere will cause it to becomes charged. The subsequentpotential field at the accelerator due to the sphere can be neglected. The angular momentum of a particle is defined in a similar way to the moment of a force. It is defined as the moment of its linear momentum, linear replacing the force. We may assume the angular momentum of a proton about point O to be conserved. Assume the mass of the proton as m_(P) and the charge on it as e. Given that the potential of the sphere increases with time and eventually reaches a constant velue. After a long time, when the potential of the sphere reaches a constant value, the trajectory of proton is correctly sketched as

An accelration produces a narrow beam of protons, each having an initial speed of v_(0) . The beam is directed towards an initially uncharges distant metal sphere of radius R and centered at point O. The initial path of the beam is parallel to the axis of the sphere at a distance of (R//2) from the axis, as indicated in the diagram. The protons in the beam that collide with the sphere will cause it to becomes charged. The subsequentpotential field at the accelerator due to the sphere can be neglected. The angular momentum of a particle is defined in a similar way to the moment of a force. It is defined as the moment of its linear momentum, linear replacing the force. We may assume the angular momentum of a proton about point O to be conserved. Assume the mass of the proton as m_(P) and the charge on it as e. Given that the potential of the sphere increases with time and eventually reaches a constant velue. The total energy (E) of a proton in the beam travelling with seed v at a distance of r (r ge R) from point O. Assuming that the sphere has acquired an electrostatic charge Q is

Thin films, including soap bubbles and oil show patterns of alternative dark and bright regions resulting from interference among the reflected light waves. If two waves are in phase, their crests and troughs will coincide. The interference will be constructive and the amplitude of resultant wave will be greater then either of constituent waves. If the two wave are not of phase by half a wavelength (180^(@)) , the crests of one wave will coincide width the troughs of the other wave. The interference will be destructive and the amplitude of the resultant wave will be less than that of either constiuent wave. 1. When incident light I, reaches the surface at point a, some of the light is reflected as ray R_(a) and some is refracted following the path ab to the back of the film. 2. At point b, some of the light is refracted out of the film and part is reflected back through the film along path bc. At point c, some of the light is reflected back into the film and part is reflected out of the film as ray R_(c) . R_(a) and R_(c) are parallel. However, R_(c) has traveled the extra distance within the film of abc. If the angle of incidence is small, then abc is approximately twice the film's thickness . If R_(a) and R_(c) are in phase, they will undergo constructive interference and the region ac will be bright. If R_(a) and R_(c) are out of phase, they will undergo destructive interference and the region ac will be dark. I. Refraction at an interface never changes the phase of the wave. II. For reflection at the interfere between two media 1 and 2, if n_(1) gt n_(2) , the reflected wave will change phase. If n_(1) lt n_(2) , the reflected wave will not undergo a phase change. For reference, n_(air) = 1.00 . III. If the waves are in phase after reflection at all intensities, then the effects of path length in the film are: Constrictive interference occurs when 2 t = m lambda // n, m = 0, 1,2,3 ,... Destructive interference occurs when 2 t = (m + (1)/(2)) (lambda)/(n) , m = 0, 1, 2, 3 ,... If the waves are 180^(@) out of the phase after reflection at all interference, then the effects of path length in the film area: Constructive interference occurs when 2 t = (m + (1)/(2)) (lambda)/(n), m = 0, 1, 2, 3 ,... Destructive interference occurs when 2 t = (m lambda)/(n) , m = 0, 1, 2, 3 ,... 72. A film with index of refraction 1.50 coats a glass lens with index of refraction 1.80. What is the minimum thickness of the thin film that will strongly reflect light with wavelength 600 nm?

HC VERMA-PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY-Exercises
  1. A totally reflecting, small plane mirror placed horizontally faces a p...

    Text Solution

    |

  2. A 100 W light bulb is placed at the centre of a spherical chamber of r...

    Text Solution

    |

  3. A sphere of radius 1.00 cm is placed in the path of a parallel beam of...

    Text Solution

    |

  4. Consider the situation described in the previous problem. Show that th...

    Text Solution

    |

  5. It is not possible for a photon to be completely absorbed by a free el...

    Text Solution

    |

  6. Two neutral particles are kept 1m apart. Suppose by some mechanism som...

    Text Solution

    |

  7. Find the maximum kinetic energy of the photoelectrons ejected when lig...

    Text Solution

    |

  8. The work function of a photoelectric material is 4.0 e V. (a) What i...

    Text Solution

    |

  9. Find the maximum magnitude of the linear momentum of a photoelectron e...

    Text Solution

    |

  10. When a metal plate is exposed to a monochromatic beam of light of wave...

    Text Solution

    |

  11. In an experiment on photoelectric effect, the stopping potential is me...

    Text Solution

    |

  12. The electric field associated with a monochromataic beam of light beco...

    Text Solution

    |

  13. The electric field associated with a light wave is given by E= E0 sin...

    Text Solution

    |

  14. The electric field at a point associated with a light wave is E=(100Vm...

    Text Solution

    |

  15. A monochromatic light source of intensity 5 m W emits (8xx10^15) photo...

    Text Solution

    |

  16. A photographic film is coated with a silver bromide layer. When light ...

    Text Solution

    |

  17. In an experiment on photoelectric effect light of wavelength 400 nm is...

    Text Solution

    |

  18. A silver ball of radius 4.8 cn is suspended by a thread in a cacuum ch...

    Text Solution

    |

  19. In an experiment on photoelectric effect, the emitter and the collecto...

    Text Solution

    |

  20. In the following arrangement y = 1.0 mm , d = 0.24 mm and D = 1.2 m. T...

    Text Solution

    |