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
The earth and the moon are attracted to each other by gravitational force. Does the earth attract the moon with a force that is greater or smaller or the same as the force with which the moon attracts the earth? Why?
State two applications of universal law of gravitation.
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 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.
Which of the following quantities remain constant in a planetary motion (consider elliptical orbits) as seen from the sun?
A uniform metal sphere of radius a and mass M is surrounded by a thin uniform spherical shell of equal mass and radius 4a (In the following figure). The centre of the shell falls on the surface of the inner sphere. Find the gravitational field at the points P1 and P2 shown in the figure.
A ball is thrown vertically upwards. It goes to a height 20 m and then returns to the ground. Taking acceleration due to gravity g to be 10 ms-2 , find :
the total time of journey of the ball .
Is the law of gravitation applicable in case of the sun and the moon?
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?
At what height above the earth's surface would the value of acceleration due to gravity be half of what it is on the surface? Take the radius of earth to be R.
Name and state the action and reaction in the following case:
A book lying on a table.
Why does a ball moving on a table top eventually stops?
Explain why:
The atmosphere does not escape.
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.
The _______ force is much weaker than other forces in nature.
Give the applications of universal law gravitation.
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.
Shown are several curves (Figure). Explain with reason, which ones amongst them can be possible trajectories traced by a projectile (neglect air friction).
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.
