which is these are the laws of Kepler?
  • The cube of the mean distance of a planet from the sun is directly proportional to the square of time it takes to move around the sun
  • Each planet revolves around the sun in such a way that the line joining the planet to the sun sweeps over equal areas in equal interval of time
  • The planets move in the elliptical orbits around the sun with sun situated on one of the foci of the elliptical orbit
  • All the above
What is true of g?
  • it is vector quantity and has unit m/s2
  • it is scalar quantity and has unit m/s2
  • it is vector quantity and has unit m/s
  • it is scalar quantity and has unit m/s
The value of g at three places A,B,C which are above the surface of the earth are in the following order A > B > C what can be said about the distance of these places from the surface of the earth
  • A > B > C
  • A=B=C
  • C> B> A
  • None of the above
There are two statements A The weight of the body is not constant and it changes with acceleration due to gravity B The mass of the objects can never be zero Which one of the following is correct?
  • A only
  • B only
  • Both A and B are correct
  • Both A and B are incorrect
Two bodies fall from the same height on the surface of the earth ? Which body will strike the surface first
  • Heavier body
  • lighter body
  • Both will reach same at the same time
  • none of these
Why will a sheet of paper fall slower than one that is crumpled into a ball?
  • The sheet of paper experience more air resistance then crumpled one
  • The crumpled one will have more gravitational force then sheet of paper
  • None of these
Two objects A and B are of mass m1 and m2 are separated by the distance r. The Gravitational force between the objects is F What will be Gravitational Force between the two objects if the mass of the one object is doubled
  • F/4
  • 2F
  • F/2
  • 4F
What will be Gravitational Force between the two objects if distance is increased two times?
  • F/4
  • 2F
  • F/2
  • 4F
What will be Gravitational Force between the two objects if distance is increased two times and both the masses are doubled?
  • F/4
  • 2F
  • F/2
  • F
A ball is thrown vertically upwards with a velocity of 49 m/s and g =9.8 m/s2 Calculate the max height it rises up to?
  • 112.5 m
  • 245 m
  • 122.5 m
  • none of these
Calculate the total time it takes to reach back to surface?
  • 20 sec
  • 15 sec
  • 5 sec
  • 10 sec
A coin and a feather are dropped together in a vacuum.
  • The coin will reach the ground first.
  • The feather will reach the ground first.
  • Both will reach the ground together.
  • The feather will not fall down.
Consider a heavenly body that has mass \(2M_e\) and radius \(2R_e\), where \(M_e\) and \(R_e\) are the mass and the radius of the earth respectively. The acceleration due to gravity at the surface of this heavenly body is
  • \(2.45m/{s^2}\)
  • \(4.9m/{s^2}\)
  • \(9.8m/{s^2}\)
  • \(19.6m/{s^2}\)
Newton’s law of gravitation is valid
  • on the earth only
  • on the moon only
  • in the laboratory only
  • everywhere
The value of G on the moon is about one-sixth of its value on the earth.
  • True
  • False
Newton's law of gravitation follows from Newton's laws of motion
  • True
  • False
The universal constant of gravitation G has the unit
  • \(N\)
  • \(m/s\)
  • \((Nm^2)/Kg^2\)
  • \(J\)
The force of gravitation between two bodies of mass 1 kg each kept at a distance of 1 m is
  • \(6.67N\)
  • \(6.67\times 10^{-9}\)
  • \(6.67\times 10^{-7}\)
  • \(6.67\times 10^{-11}N\)
Mass and weight are measured in different units.
  • True
  • False
Two particles are kept at a distance \(r\). The gravitational force between them is proportional to
  • \(r\)
  • \(r^2\)
  • \( \frac{1}{r}\)
  • \( \frac{1}{r^2}\)
0 h : 0 m : 1 s

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