CBSE
Assertion: Planet is a heavenly body revolving round the sun.
Reason: Star is luminous body made of gaseous material.
If both the assertion and reason are true and reason is a correct explanation of the assertion.
If both assertion and reason are true but assertion is not a correct explanation of the assertion.
If the assertion is true but the reason is false.
If both assertion and reason are false.
Escape velocity of a rocket is 11.2 km/sec. It is released at an angle of 45°. Its escape velocity is
11.2 m/sec
11.2 km/sec
11.2 km/sec
22.3 km/sec
Hubble's law is related with
comet
speed of galaxy
black hole
planetary motion
The equivalent resistance between A and C of the given circuit, is
8 Ω
Ω
Ω
The orbital velocity of an artificial satellite in a circular orbit above the earth's surface at a distance equal to radius of earth is v. For a satellite orbiting at an altitude half of earth's radius, orbital velocity is
v
v
v
The condition for a uniform spherical mass m of radius r to be a black hole is [ G = gravitational constant and g = acceleration due to gravity ]
Kepler's second law is based on
Newton's first law
special theory of relativity
Newton's second law
Conservation of angular momentum
What is the dimensional formula for the gravitational constant?
[ M-1 L3 T-2 ]
[ M-1 L3 T-1 ]
[ M-2 L3 T-2 ]
[ M-2 L-1 T3 ]
If vο be the orbital velocity of satellite in a circular orbit close to the earth's surface and ve is the escape velocity from the earth, then relation between the two is
vο = ve
ve =
ve = vο
ve = 2 vο
The velocity with which a projectile must be fired so that it escapes earth's gravitation does not depend on
mass of the earth
mass of the projectile
radius of the projectile's orbit
gravitational constant