Advertisements
Advertisements
प्रश्न
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 .
Advertisements
उत्तर
Given, maximum height reached, s = 20 m
Acceleration due to gravity, g = 10 m/s2
Now total time for which the ball remains in air, t = 2u/g.
Or, t = 2 (20)/(10).
Or, t = 4s.
APPEARS IN
संबंधित प्रश्न
How does the force of gravitation between two objects change when the distance between them is reduced to half?
Can you think of two particles which do not exert gravitational force on each other?
Let V and E be the gravitational potential and gravitational field at a distance r from the centre of a uniform spherical shell. Consider the following two statements :
(A) The plot of V against r is discontinuous.
(B) The plot of E against r is discontinuous.
A tunnel is dug along a diameter of the earth. Find the force on a particle of mass m placed in the tunnel at a distance x from the centre.
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 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.
What does a force do in the following case?
You catch a kicked ball.
Gravity is another kind of ________. It exerts all through the ________. The Sun's gravity keeps the ___________ in their orbits. Gravity can only be felt with very large ________.
Answer the following question.
State Newton’s law of gravitation and express it in vector form.
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.
