Advertisements
Advertisements
Question
Molecules in air in the atmosphere are attracted by gravitational force of the earth. Explain why all of them do not fall into the earth just like an apple falling from a tree.
Advertisements
Solution
Air molecules in the atmosphere are attracted by the gravitational force of the earth but they do not fall into the earth due to the reason that the molecules in air have some random motion due to temperature, so their resultant motion is not exactly the vertically downward direction.
But in the case of apples, only vertical motion dominates because of being heavier than air molecules. But due to gravity, the density of air is more near to the earth than the density as we go up.
APPEARS IN
RELATED QUESTIONS
What is the magnitude of the gravitational force between the earth and a 1 kg object on its surface? (Mass of the earth is 6 × 1024 kg and radius of the earth is 6.4 × 106 m).
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?
If you compare the gravitational force on the Earth due to the Sun to that due to the Moon, you would find that the Sun’s pull is greater than the Moon’s pull. (You can check this yourself using the data available in the succeeding exercises). However, the tidal effect of the Moon’s pull is greater than the tidal effect of Sun. Why?
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.
Can we apply Newton’s third law to the gravitational force ? Explain your answer.
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 ?
A person sitting in a chair in a satellite feels weightless because
Which of the following quantities remain constant in a planetary motion (consider elliptical orbits) as seen from the sun?
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.
Define one Newton. How much maximum acceleration can it produce in a mass of 1 kg?
Name and state the action and reaction in the following case:
Hammering a nail.
Two equal and opposite forces acting at the same point on a stationary body. Will the body move? Give reason to explain your answer.
State Newton's law of gravitation. What is the difference between:
g and G?
An apple falls towards the earth due to its gravitational force. The apple also attracts the earth with the same force. Why do we not see the earth rising towards the apple? Explain.
Solve the following problem.
Find the gravitational force between the Sun and the Earth.
Given Mass of the Sun = 1.99 × 1030 kg
Mass of the Earth = 5.98 × 1024 kg
The average distance between the Earth and the Sun = 1.5 × 1011 m.
State the universal law of gravitation and derive its mathematical expression.
We can shield a charge from electric fields by putting it inside a hollow conductor. Can we shield a body from the gravitational influence of nearby matter by putting it inside a hollow sphere or by some other means?
Who measured the value of the Universal Gravitational Constant G using the Cavendish balance?
