A planet orbits the sun in an elliptical path. Which of the following statements
Practice Questions
Q1
A planet orbits the sun in an elliptical path. Which of the following statements is true regarding its angular momentum?
It is constant.
It varies with distance from the sun.
It is zero at perihelion.
It is maximum at aphelion.
Questions & Step-by-Step Solutions
A planet orbits the sun in an elliptical path. Which of the following statements is true regarding its angular momentum?
Step 1: Understand what angular momentum is. Angular momentum is a measure of how much motion an object has as it rotates around a point, in this case, the sun.
Step 2: Recognize that the planet is moving in an elliptical path around the sun. This means its distance from the sun changes as it orbits.
Step 3: Identify that angular momentum depends on the mass of the planet, its velocity, and its distance from the sun.
Step 4: Note that there are no external forces (like friction) acting on the planet in space that would change its motion significantly.
Step 5: Understand the concept of conservation of angular momentum. This means that if no external torque (twisting force) is acting on the planet, its angular momentum will remain constant.
Step 6: Conclude that since there is no external torque acting on the planet, its angular momentum about the sun is conserved.
Angular Momentum Conservation – Angular momentum is conserved in a system where no external torques are acting, which applies to a planet orbiting the sun.
Elliptical Orbits – Planets follow elliptical orbits as described by Kepler's laws, affecting their velocity and angular momentum.
Torque – Torque is a measure of the force that can cause an object to rotate about an axis; in this case, the absence of external torque is crucial for conservation.
