Circular Motion and Orbits

Front

What is Kepler's Third Law of Planetary Motion?

Back

Kepler's Third Law states that the square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit. This can be expressed as T² ∝ r³, where T is the orbital period and r is the average distance from the sun.

Front

Define centripetal force.

Back

Centripetal force is the net force that acts on an object moving in a circular path, directed towards the center of the circle. It is necessary for maintaining circular motion.

Front

What role does friction play in circular motion?

Back

Friction provides the necessary centripetal force for an object to move in a circular path. Without friction, an object would not be able to change direction and would slide off in a straight line.

Front

How do you calculate the orbital velocity of an object in circular orbit?

Back

Orbital velocity (v) can be calculated using the formula v = √(GM/r), where G is the gravitational constant, M is the mass of the central body, and r is the distance from the center of the mass to the object.

Front

What is the formula for gravitational force between two masses?

Back

The gravitational force (F) between two masses can be calculated using Newton's law of universal gravitation: F = G(m1*m2)/r², where G is the gravitational constant, m1 and m2 are the masses, and r is the distance between the centers of the two masses.

Front

What is the significance of the term 'orbital radius'?

Back

Orbital radius is the distance from the center of the mass being orbited to the object in orbit. It is crucial for determining the gravitational force and orbital period.

Front

How does mass affect weight on different planets?

Back

Weight is the force of gravity acting on an object, which depends on both the mass of the object and the gravitational acceleration of the planet. If a planet has a greater radius but the same mass as Earth, the weight will be less due to lower gravitational acceleration.

Front

What is the relationship between radius and orbital period according to Kepler's laws?

Back

According to Kepler's laws, as the radius of an orbit increases, the orbital period also increases. This means that planets further from the sun take longer to complete an orbit.

Front

Define normal force in the context of circular motion.

Back

Normal force is the force exerted by a surface to support the weight of an object resting on it. In circular motion, it can change depending on the object's speed and the radius of the curve.

Front

What is the formula for calculating the normal force on an object in circular motion?

Back

The normal force (N) can be calculated using the formula N = mg + (mv²/r), where m is the mass, g is the acceleration due to gravity, v is the velocity, and r is the radius of curvature.