Home
Class 12
PHYSICS
Figure elliptical path abcd of a planet ...


Figure elliptical path abcd of a planet around the sun S such that the area of Delta csa is `(1)/(4)` the area of the ellipse, (see figure) with db as the semimajor axis, and ca as the semiminor axis if `t_(1)` is the time taken for planet to go over path abc and `t_(2)` for path taken over cda then:

A

`t_(1)=4t_(2)`

B

`t_(1)=3t_(2)`

C

`t_(1)=t_(2)`

D

`t_(1)=2t_(2)`

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • GRAVITATION

    ALLEN |Exercise Exercise 5 B (Previous Year Questions)|9 Videos

  • GRAVITATION

    ALLEN |Exercise Illustration|34 Videos

  • GRAVITATION

    ALLEN |Exercise Exercise 4 B (Brain Storming Subjective Exercise)|20 Videos

  • GEOMETRICAL OPTICS

    ALLEN |Exercise subjective|14 Videos

  • KINEMATICS-2D

    ALLEN |Exercise Exercise (O-2)|47 Videos

Similar Questions

Explore conceptually related problems

The figure shows elliptical orbit of a planet m about the sun S. the shaded area SCD is twice the shaded area SAB. If t_(1) be the time for the planet to move from C to D and t_(2) is the time to move from A to B, then:

The figure shows elliptical orbit of a planet m about the sun S. the shaded area SCD is twice the shaded area SAB. If t_(1) be the time for the planet to move from C to D and t_(2) is the time to move from A to B, then:

The figure shows elliptical orbit of a planet m about the sun S. The shaded area SCD is twice the shaded are SAB. If t_1 is the time for the planet to move from C to D and t_2 is the time to move from A to B then ......

A ray of light travelling with a speed c leaves point 1 shown in figure and is reflected to point 2. The ray strikes the reflecting surface at a distance x from point 1. According to Fermat's principle of least time, among all possible paths between two points , the one actually taken by a ray of light is that for which the time taken is the least (In fact there are some cases in which the time taken by a ray is maximum rather than a minimum). Find the time for the ray to reach from point 1 to point 2.

A ray of light travelling with a speed c leaves point 1 shown in figure and is reflected to point 2. The ray strikes the reflecting surface at a distance x from point 1. According to Fermat's principle of least time, among all possible paths between two points , the one actually taken by a ray of light is that for which the time taken is the least (In fact there are some cases in which the time taken by a ray is maximum rather than a minimum). Which of the following statement is in accordance with Fermat's principle

A ray of light travelling with a speed c leaves point 1 shown in figure and is reflected to point 2. The ray strikes the reflecting surface at a distance x from point 1. According to Fermat's principle of least time, among all possible paths between two points , the one actually taken by a ray of light is that for which the time taken is the least (In fact there are some cases in which the time taken by a ray is maximum rather than a minimum). Under what condition is time taken least?

The velocity of a particle moving in the positive direction of the x axis varies as v=alphasqrtx , where alpha is a positive constant. Assuming that at the moment t=0 the particle was located at the point x=0 , find: (a) the time dependence of the velocity and the acceleration of the particle, (b) the mean velocity of the particle averaged over the time that the particle takes to cover the first s metres of the path.

Length of a year on a planet is the duration in which it completes one revolution around the sun. Assume path of the planet known as orbit to be circular with sun at the centre. The length T of a year of a planet orbiting around the sun in circular orbit depends on universal gravitational constant G, mass m_(s) of the sun and radius r of the orbit. if TpropG^(a)m_(s)^(b)r^(c) find value of a+b+2c.

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?

Two metallic plate A and B , each of area 5 xx 10^(-4)m^(2) , are placed parallel to each at a separation of 1 cm plate B carries a positive charge of 33.7 xx 10^(-12) C A monocharonatic beam of light , with photoes of energy 5 eV each , starts falling on plate A at t = 0 so that 10^(16) photons fall on it per square meter per second. Assume that one photoelectron is emitted for every 10^(6) incident photons fall on it per square meter per second. Also assume that all the emitted photoelectrons are collected by plate B and the work function of plate A remain constant at the value 2 eV Determine (a) the number of photoelectrons emitted up to i = 10s, (b) the magnitude of the electron field between the plate A and B at i = 10 s, and (c ) the kinetic energy of the most energotic photoelectrons emitted at i = 10 s whenit reaches plate B Negilect the time taken by the photoelectrons to reach plate B Take epsilon_(0) = 8.85 xx 10^(-12)C^(2)N- m^(2)

ALLEN -GRAVITATION-Exercise 5 A (Previous Year Questions)
  1. The time period of an earth satellite in circular orbit is independent...

    Text Solution

    |

  2. Suppose the gravitational force varies inversely as the n^(th) power o...

    Text Solution

    |

  3. Suppose the gravitational force varies inversely as the n^(th) power o...

    Text Solution

    |

  4. Average density of the earth

    Text Solution

    |

  5. The change in the value of g at a height h above the surface of the ea...

    Text Solution

    |

  6. A particle of mass 10g is kept on the surface of a uniform sphere of m...

    Text Solution

    |

  7. If gE and gM are the acceleration due to gravity on the surfaces of th...

    Text Solution

    |

  8. A planet in a distant solar systyem is 10 times more massive than the ...

    Text Solution

    |

  9. This question contains Statement -1 and Stantement -2 Of the four choi...

    Text Solution

    |

  10. The height at which the acceleration due to gravity becomes g/9 in ter...

    Text Solution

    |

  11. Two bodies of masses m and 4m are placed at a distance r. The gravitat...

    Text Solution

    |

  12. Two particles of equal mass 'm' go around a circle of radius R under t...

    Text Solution

    |

  13. The mass of a spaceship is 1000kg. It is to be launched from the earth...

    Text Solution

    |

  14. Four particles, each of mass M and equidistant from each other, move a...

    Text Solution

    |

  15. From a solid sphere of mass M and radius R, a spherical portion of rad...

    Text Solution

    |

  16. A very long (length L) cylindrical galaxy is made of uniformly distrib...

    Text Solution

    |

  17. The correct variation of gravitational potential V with radius r measu...

    Text Solution

    |

  18. A satellite is revolving in a circular orbit at a height 'h' from the ...

    Text Solution

    |

  19. Figure elliptical path abcd of a planet around the sun S such that the...

    Text Solution

    |

  20. An astronaut of mass m is working on a satellite orbitting the earth a...

    Text Solution

    |