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

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

Question 2: Describe the mechanism of how gravity acts between two objects.

Answer: Gravity acts between two objects with mass, pulling them toward each other. The strength of this force depends on their masses and the distance between them, according to Newton's Law of Universal Gravitation.

Question 3: What is weight, and how is it related to gravity?

Answer: Weight is the force exerted on an object due to gravity. It is calculated as the mass of the object multiplied by the acceleration due to gravity (W = m × g).

Question 1: An object with a mass of 10 kg is on Earth. Calculate its weight in newtons (N). (Use g = 9.8 m/s²).

Answer: W = m × g = 10 kg × 9.8 m/s² = 98 N

Question 2: A satellite orbits at an altitude where the acceleration due to gravity is 7.5 m/s². If the satellite's mass is 500 kg, what is the gravitational force (in newtons) acting on it?

Answer: F = m × g = 500 kg × 7.5 m/s² = 3750 N

Question 1: Describe a simple experiment to demonstrate the effect of gravity on different objects. Include the variables involved and safety precautions.

Answer: One simple experiment is dropping objects of different masses (e.g., a feather and a stone) from the same height to observe their fall. Variables include object mass (independent) and fall time (dependent). Safety precautions include ensuring a clear area and using soft landing surfaces to prevent injuries.

Question 2: Identify the independent and dependent variables in an experiment measuring the time it takes for different objects to fall from the same height.

Answer: Independent variable: type of object (mass, shape, material). Dependent variable: time taken to fall.

Question 1: In an experiment, a 2 kg object and a 5 kg object are dropped from the same height. Both reach the ground at the same time. Explain why this occurs based on the principles of gravity.

Answer: According to physics, in a vacuum or absent air resistance, all objects fall at the same acceleration regardless of mass. Therefore, both objects reach the ground simultaneously because gravity accelerates all objects equally.

Question 1: Explain how gravity affects the motion of planets in the solar system. Include the role of gravity in maintaining planetary orbits. (6 marks)

Answer: Gravity is the force of attraction between the Sun and planets. It provides the centripetal force necessary to keep planets in orbit around the Sun. Without gravity, planets would drift away into space. The balance between gravitational pull and the planets' velocity results in stable orbits.

Question 2: A 50 kg object experiences a gravitational force of 490 N. What is the acceleration due to gravity at this location?

Answer: g = F / m = 490 N / 50 kg = 9.8 m/s²

Question 1: Describe how understanding gravity is important in designing spacecraft and satellite orbits.

Answer: Understanding gravity helps engineers calculate the correct velocity and trajectory for spacecraft and satellites to maintain stable orbits, avoid falling back to Earth, or reach other planets. Precise calculations ensure safe and efficient space missions.

Question 2: Explain the significance of gravity in everyday life and technology, providing one example.

Answer: Gravity is essential for many daily activities, such as walking, and for technological applications like the design of elevators and roller coasters that rely on gravitational principles to operate safely.