Question 1: A velocity-time graph shows how an object's velocity changes over time. The gradient of the graph represents the object's acceleration, and the area under the graph indicates the displacement during that time interval.

Answer: A velocity-time graph illustrates the change in velocity over time; gradient = acceleration; area under the curve = displacement.

Question 1: Define velocity in the context of motion graphs.

Answer: Velocity is the speed of an object in a specified direction, represented on a velocity-time graph by the value along the vertical axis.

Question 2: Explain what a horizontal straight line on a velocity-time graph indicates about an object's motion.

Answer: It indicates that the object is moving at a constant velocity, with no acceleration.

Question 1: A car accelerates uniformly from 0 m/s to 20 m/s in 10 seconds. Calculate its acceleration in m/s². Use the formula: acceleration = (final velocity - initial velocity) / time.

Answer: 2 m/s²

Question 2: A cyclist travels at a constant velocity of 15 m/s for 5 minutes. Calculate the total displacement in metres. (Note: 1 minute = 60 seconds).

Answer: 4500 metres

Question 1: Describe a simple experiment to measure the velocity of a toy car over a period of time. Include the variables involved and safety precautions.

Answer: Set up a toy car on a flat track, use a stopwatch to record time at specific intervals, measure the distance travelled at each interval, and calculate velocity. Variables include initial speed, acceleration, and track length. Safety precautions involve ensuring the track is secure and free of obstructions, and handling the stopwatch carefully.

Question 1: A vehicle's velocity increases from 0 m/s to 30 m/s over 15 seconds, then remains constant. Describe the shape of the velocity-time graph and interpret the motion phases.

Answer: The graph rises linearly from 0 to 30 m/s over 15 seconds, indicating uniform acceleration. Then, the graph is a horizontal line, indicating constant velocity. The object accelerates initially, then moves at a steady speed.

Question 1: Explain how velocity-time graphs are used in the automotive industry to improve vehicle safety features such as airbags and anti-lock braking systems.

Answer: Velocity-time graphs help engineers analyse a vehicle's deceleration during braking and collision impacts, enabling design of safety features like airbags and anti-lock braking systems to respond effectively during sudden stops or crashes.

Question 1: What does a steep positive gradient on a velocity-time graph indicate?

Answer: Uniform acceleration

Question 2: If the area under a velocity-time graph is zero, what does this imply about the displacement?

Answer: Zero displacement