Question 1: Define gravity and explain how it affects objects on Earth.

Answer: Gravity is a force of attraction between two masses. On Earth, it pulls objects toward the center, giving them weight and causing objects to fall when dropped.

Question 2: Describe the mechanism by which gravity causes planets to orbit stars.

Answer: Gravity is a mutual attraction between a star and a planet. The gravitational pull of the star keeps the planet in orbit, balancing the planet's tendency to move in a straight line.

Question 1: Calculate the gravitational force between Earth (mass = 5.97×10²⁴ kg) and the Moon (mass = 7.35×10²² kg) separated by a distance of 384,400 km.

Answer: Approximately 1.98×10²⁰ N

Question 2: If the distance between two objects is doubled, how does the gravitational force change?

Answer: The gravitational force decreases by a factor of four because force is inversely proportional to the square of the distance.

Question 1: Design a simple experiment to demonstrate that gravity acts equally on objects of different masses in a vacuum chamber. List the variables involved and safety precautions.

Answer: In a vacuum chamber, drop objects of different masses simultaneously and observe that they hit the bottom at the same time. Variables: mass of objects (independent), time to hit the bottom (dependent), air resistance (controlled). Safety precautions include ensuring the chamber is properly sealed and handling objects carefully.

Question 2: Explain how gravity is utilized in satellite technology and the importance of gravitational calculations in satellite deployment.

Answer: Gravity keeps satellites in orbit around Earth. Accurate gravitational calculations are essential to determine the correct launch velocity and orbital parameters, ensuring the satellite remains in its intended path.

Question 1: A skydiver jumps from a plane at 10,000 meters. Assuming negligible air resistance, estimate the time taken to reach the ground using the acceleration due to gravity (9.8 m/s²).

Answer: Approximately 45 seconds

Question 2: Describe the role of gravity in the formation of planets and the importance of gravitational forces in preventing celestial bodies from drifting apart.

Answer: Gravity is fundamental to planetary formation, pulling dust and gas together to form planets. It also maintains the structure of solar systems by exerting a force that keeps celestial bodies in orbit, preventing them from drifting away into space.