Advertisements
Advertisements
प्रश्न
A particle of mass 100 g is kept on the surface of a uniform sphere of mass 10 kg and radius 10 cm. Find the work to be done against the gravitational force between them to take the particle away from the sphere.
Advertisements
उत्तर
The work done against the gravitational force to take the particle away from the sphere to infinity is equal to the difference between the potential energy of the particle at infinity and potential energy of the particle at the surface of the sphere.

\[\therefore W = 0 - \left( - \frac{G \times 10 \times 0 . 1}{1 \times 0 . 1} \right)\]
\[ = \frac{6 . 67 \times {10}^{- 11} \times 1}{1 \times 0 . 1}\]
\[ = 6 . 67 \times {10}^{- 10} J\]
APPEARS IN
संबंधित प्रश्न
A person brings a mass of 1 kg from infinity to a point A. Initially the mass was at rest but it moves at a speed of 2 m s −1 as it reaches A. The work done by the person on the mass is −3 J. The potential at A is
A body is suspended from a spring balance kept in a satellite. The reading of the balance is W1 when the satellite goes in an orbit of radius R and is W2 when it goes in an orbit of radius 2 −R.
The law of gravitation gives the gravitational force between :
The acceleration produced by a force in an object is directly proportional to the applied _________ And inversely proportional to the _________ Of the object.
How will the force of gravitation between two objects change if the distance between them is:
Infinite
A ball is thrown up with a speed of 4.9 ms-1.
Calculate the maximum height it would gain before it begins to fall.
A ball is thrown up with a speed of 4.9 ms-1.
Calculate the time it takes to reach this height.
Where will you weigh more: at the moon's surface or at the earth's surface?
Name and state the action and reaction in the following case:
A person walking on the ground.
What is the difference between gravity and gravitation?
Answer the following question.
State Newton’s law of gravitation and express it in vector form.
Law of gravitation gives the gravitational force between
Particles of masses 2M, m and M are respectively at points A, B and C with AB = ½ (BC). m is much-much smaller than M and at time t = 0, they are all at rest (Figure). At subsequent times before any collision takes place ______.

How is the gravitational force between two point masses affected when they are dipped in water keeping the separation between them the same?
The gravitational force between a hollow spherical shell (of radius R and uniform density) and a point mass is F. Show the nature of F vs r graph where r is the distance of the point from the centre of the hollow spherical shell of uniform density.
Complete the chart below.
| F(N) | M1(kg) | M2(kg) | D(m) |
| (a) | 50 | 84 | 02 |
| 16 × 109 | 1.63 × 1022 | (b) | 34 |
Observe the figure and answer the questions:

- State Newton's universal law of gravitation.
- If the distance between the two bodies is tripled, how will the gravitational force between them change?
- What will happen to gravitational force, if mass of one of the object is doubled?
If the mass of one object is doubled and distance remains the same, the gravitational force will ______.
A hollow spherical shell of uniform density exerts what gravitational force on a point mass placed inside it?
