1. | \(2\) km/s | 2. | \(2\sqrt2\) km/s |
3. | \(2(\sqrt2-1)\) km/s | 4. | \(2(\sqrt2+1)\) km/s |
Statement I: | The gravitational force acting on a particle depends on the electric charge of the particle. |
Statement II: | The gravitational force on an extended body can be calculated by assuming the body to be a particle 'concentrated' at its centre of mass and applying Newton's law of gravitation. |
1. | Statement I is incorrect and Statement II is correct. |
2. | Both Statement I and Statement II are correct. |
3. | Both Statement I and Statement II are incorrect. |
4. | Statement I is correct and Statement II is incorrect. |
1. | \(\Large\frac{GM^2}{4R^2}\) | 2. | \(\Large\frac{GM^2}{R^2}\) |
3. | \(\Large\frac{GM^2}{16R^2}\) | 4. | \(\Large\frac{4GM^2}{R^2}\) |
1. | \(\Large\frac{2GMm}{r^2(M+m)}\) | 2. | \(\Large\frac{GMm}{r^2(M+m)}\) |
3. | \(\Large\frac{G(M\text - m)}{r^2}\) | 4. | \(\Large\frac{G(M\text + m)}{r^2}\) |
Two identical-mass planets (mass: \(m\)) move around a Star (mass: \(M\)) in a circular orbit of radius \(r,\) in a symmetrical manner. The orbital speed of the planets is:
1. \(\sqrt{\dfrac{2GM}{r}}\)
2. \(\sqrt{\dfrac{5GM}{4r}}\)
3. \(\sqrt{\dfrac{G(M+m)}{r}}\)
4. \(\sqrt{\dfrac{G[M+(m/4)]}{r}}\)
If a particle is projected vertically upward with a speed \(u,\) and rises to a maximum altitude \(h\) above the earth's surface then:
(\(g=\) acceleration due to gravity at the surface)
1. | \(h>\dfrac{u^2}{2g}\) |
2. | \(h=\dfrac{u^2}{2g}\) |
3. | \(h<\dfrac{u^2}{2g}\) |
4. | Any of the above may be true, depending on the earth's radius |
1. | \(mr\) | 2. | \(\dfrac{m}{r}\) |
3. | \(m\sqrt r\) | 4. | \(\dfrac{m}{\sqrt r}\) |
If the axis of rotation of the earth was extended into the space, then it would pass close to:
1. the moon
2. the sun
3. the pole star
4. the center of mass of all the planets in the solar system