Gravitation Tes...

The ratio of escape velocity of a tennis ball to that of a basket ball on the surface of the earth is

A satellite S is moving in an elliptical orbit around the earth. The mass of the satellite is very small compared to the mass of the earth

The distance from the surface of the earth at which above and below the surface acceleration due to gravity is same will be

A satellite in earth orbit experiences a small drag force as it enters the earth's atmosphere. Two students were asked consequence of this
Student-A : The satellite would slow down as, it spirals towards earth due to work of frictional force.
Student-B : The satellite speed up due to earths gravitational pull as it spirals towards earth.

Satellites A and B are orbiting around the earth in orbits of ratio $$R$$ and $$4R$$ respectively. The ratio of their areal velocities is

A planet of radius $$R = 1/10 \times $$ (radius of Earth) has the same mass density as Earth. Scientists dig a well of depth $$R/5$$ on it and lower a wire of the same length and of linear mass density $$10^{-3} kgm^{-3}$$ into it. If the wire is not touching anywhere, the force applied at the top of the wire by a person holding it in place is (take the radius of Earth $$= 6 \times 10^6 m$$ and the acceleration due to gravity on Earth is $$10 ms^{-2}$$)

Two planets  $$A$$  and $$B$$  have the same material density. If the radius of  $$A$$  is twice that of B, then the ratio of the escape velocity $$\displaystyle \dfrac{V_A}{V_B}$$ is

A planet revolves about the sun in elliptical orbit. The arial velocity $$\displaystyle \left ( \frac{dA}{dt} \right )$$ of the planet is $$4.0 \times 10^{16} m^2/s$$. The least distance between planet and the sun is $$2 \times 10^{12}$$m. Then the maximum speed of the planet in km/s is

A (nonrotating) star collapses onto itself from an initial radius R$$_i$$ with its mass remaining unchanged. Which curve in figure best gives the gravitational acceleration a$$_g$$ on the surface of the star as a function of the radius of the star during the collapse?

Select the correct choice(s)