Advertisements
Advertisements
प्रश्न
Answer the following:
You can shield a charge from electrical forces by putting it inside a hollow conductor. Can you shield a body from the gravitational influence of nearby matter by putting it inside a hollow sphere or by some other means?
Advertisements
उत्तर १
No
Gravitational influence of matter on nearby objects cannot be screened by any means. This is because gravitational force unlike electrical forces is independent of the nature of the material medium. Also, it is independent of the status of other objects.
उत्तर २
No. Gravitational forces are independent of medium. A body cannot be shielded from the gravitational influence of nearby matter.
APPEARS IN
संबंधित प्रश्न
Choose the correct alternative:
Acceleration due to gravity increases/decreases with increasing depth. (assume the earth to be a sphere of uniform density).
Choose the correct answer from among the given ones:
For the problem 8.10, the direction of the gravitational intensity at an arbitrary point P is indicated by the arrow (i) d, (ii) e, (iii) f, (iv) g.
A rocket is fired from the earth towards the sun. At what distance from the earth’s centre is the gravitational force on the rocket zero? Mass of the sun = 2 ×1030 kg, mass of the earth = 6 × 1024 kg. Neglect the effect of other planets etc. (orbital radius = 1.5 × 1011 m).
How will you ‘weigh the sun’, that is estimate its mass? The mean orbital radius of the earth around the sun is 1.5 × 108 km.
Universal law of gravitation states that every object exerts a gravitational force of attraction on every other object. If this is true, why don’t we notice such forces ? Why don’t the two objects in a room move towards each other due to this force ?
Suppose the gravitational potential due to a small system is k/r2 at a distance r from it. What will be the gravitational field? Can you think of any such system? What happens if there were negative masses?
Explain the following:
People often shake the branches of a tree for getting down its fruits.
What does a force do in the following case?
You catch a kicked ball.
Why does a ball moving on a table top eventually stops?
Explain the difference between g and G.
State Newton's law of gravitation. What is the difference between:
Gravity and gravitation
The distance-time values for an object moving along straight line are given below:
| Time (s) | Distance (m) |
| 0 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 27 |
Show that gravity decreases at higher altitudes.
Answer the following question.
What are the dimensions of the universal gravitational constant?
Answer the following question.
State Newton’s law of gravitation and express it in vector form.
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.
Six point masses of mass m each are at the vertices of a regular hexagon of side l. Calculate the force on any of the masses.
The acceleration of the Moon towards the Earth is approximately ______.
If the distance between two objects is doubled, the gravitational force becomes ______.
The gravitational force between two objects acts in which direction?
