Question 1: Define terminal velocity in your own words.

Answer: The constant speed that a freely falling object reaches when the force of gravity is balanced by the drag force of the fluid, resulting in zero acceleration.

Question 2: List the main forces acting on an object falling at terminal velocity.

Answer: Gravity (weight) and drag (air resistance).

Question 3: At terminal velocity, what is the net force acting on the object?

Answer: Zero, because the forces are balanced.

Question 4: Which factors influence the value of terminal velocity? Select all that apply.

Answer:

Question 5: Explain how increasing the surface area of an object affects its terminal velocity.

Answer: Increasing surface area increases drag force, which reduces the terminal velocity, causing the object to fall more slowly.

Question 6: Calculate the terminal velocity of a skydiver with a mass of 80 kg, a drag coefficient of 1.0, a cross-sectional area of 0.7 m², falling through air with a density of 1.2 kg/m³. Use the formula: v = sqrt((2mg) / (ρA Cd)).

Answer: v = sqrt((2 * 80 * 9.8) / (1.2 * 0.7 * 1.0)) ≈ 54.4 m/s

Question 7: Describe a simple experiment to demonstrate how terminal velocity can be observed in the classroom.

Answer: Drop objects of different shapes and sizes from a fixed height in a controlled environment, and measure the time taken to reach the ground to observe when the falling speed stabilises, indicating terminal velocity.

Question 8: Identify two variables that could be changed in an experiment to see their effect on terminal velocity, and specify potential safety precautions.

Answer: Variables: mass of the object and surface roughness. Safety precautions include ensuring secure attachment of objects, clear area below, and protective gear if necessary.

Question 9: Analyse why different objects (e.g., a feather vs. a metal ball) reach different terminal velocities.

Answer: Different objects have different masses, shapes, and surface areas, affecting the drag force and therefore their terminal velocities.

Question 10: Explain how understanding terminal velocity is important in industries such as parachuting or designing safety equipment.

Answer: Knowing terminal velocity helps engineers design parachutes that slow descent safely, ensuring that impact forces are manageable. It also aids in creating safety gear that minimises injury by controlling falling speeds.