Circular Motion and Gravitation

Front

What is centripetal acceleration?

Back

Centripetal acceleration is the acceleration directed towards the center of a circular path, experienced by an object moving in a circle at a constant speed due to the constant change in direction.

Front

Why do objects experience centripetal acceleration even though they can have a constant speed?

Back

Because they are constantly changing direction and hence, velocity changes, and that net change is directed inward.

Front

What is the formula for the period of an object in circular motion?

Back

The period (T) is the time taken for one complete revolution, calculated as T = total time / number of revolutions.

Front

If a washing machine drum rotates 1800 times in 3 minutes, what is the period?

Back

0.1 s.

Front

What is the relationship between velocity and circular motion?

Back

The velocity of an object in circular motion is always tangent to the circle at any point.

Front

The velocity is always _____ to the line of a circle.

Back

tangent.

Front

What is gravitational acceleration near the surface of a planet?

Back

Gravitational acceleration (g) is given by the formula g = GM/R², where G is the gravitational constant, M is the mass of the planet, and R is its radius.

Front

A mass m is released just above the surface of a planet with mass M and radius R. What is its initial gravitational acceleration?

Back

G M / R².

Front

What happens to the speed of a planet as it moves in an elliptical orbit?

Back

A planet moves faster when it is closer to the sun (perihelion) and slower when it is farther away (aphelion) due to the conservation of angular momentum.

Front

What is the law of universal gravitation?

Back

The law states that every point mass attracts every other point mass with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.