Question 1: Define gravity and explain its role in the Solar System.

Answer: Gravity is the force of attraction between two objects with mass. In the Solar System, gravity keeps planets in orbit around the Sun and governs the motion of celestial bodies.

Question 2: Describe the mechanism by which gravity influences the motion of planets around the Sun.

Answer: Gravity exerts an attractive force that pulls planets towards the Sun. This force provides the necessary centripetal force for planets to follow circular or elliptical orbits.

Question 1: Calculate the gravitational force between the Earth and the Moon. Use the formula F = G * (m1 * m2) / r², where G = 6.674 x 10⁻¹¹ N·m²/kg², m₁ = 5.972 x 10²4 kg (Earth), m₂ = 7.348 x 10²2 kg (Moon), and r = 3.844 x 10⁸ meters (distance between Earth and Moon).

Answer: F = 6.674 x 10⁻¹¹ * (5.972 x 10²4 * 7.348 x 10²2) / (3.844 x 10⁸)² ≈ 1.98 x 10²0 Newtons

Question 2: If the mass of a satellite is 1000 kg and it orbits at a distance of 700 km above Earth's surface, what is the gravitational force acting on it? (Earth's mass = 5.972 x 10²4 kg, radius = 6,371 km, G = 6.674 x 10⁻¹¹ N·m²/kg²).

Answer: F = G * (mass of Earth * satellite mass) / (distance from Earth's center)² Distance from Earth's center = 6,371 km + 700 km = 7,071 km = 7.071 x 10⁶ meters F = 6.674 x 10⁻¹¹ * (5.972 x 10²4 * 1000) / (7.071 x 10⁶)² ≈ 7.97 Newtons

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

Answer: One possible experiment is dropping objects of different masses (e.g., a feather and a rock) from the same height to observe their fall. Variables include object mass, height, and air resistance. Safety precautions involve ensuring the area below is clear and using appropriate protective gear if necessary.

Question 1: A satellite orbits Earth at an altitude where the gravitational force is 90% of what it is on the Earth's surface. Explain what this indicates about its distance from Earth compared to the surface.

Answer: It indicates that the satellite is farther from Earth's center than at the surface. Since gravitational force decreases with distance, being at 90% of the surface gravity means it is at a higher altitude.

Question 1: Explain how understanding gravity is essential in planning space missions and satellite launches.

Answer: Understanding gravity allows scientists to calculate orbital trajectories, launch windows, and fuel requirements. Precise knowledge of gravitational forces ensures satellites and spacecraft can reach their destinations safely and efficiently.

Question 2: Discuss how gravity affects everyday life on Earth, providing at least two examples.

Answer: Gravity keeps us anchored to the Earth's surface, enabling us to walk and stand. It also causes objects to fall when dropped and influences ocean tides due to the gravitational pull of the Moon.