A golf ball has a mass of 46 g and is initially stationary - AQA - A-Level Physics - Question 25 - 2021 - Paper 1

To find the kinetic energy (KE) of the golf ball immediately after it is hit, we need to calculate the work done on the ball by the force applied during the time interval.

1. Determine the Force Applied: From the graph, we can see the maximum force acting on the ball is around 0.7 kN (or 700 N).

2. Convert Mass of the Ball: The mass of the golf ball is given as 46 g which needs to be converted to kilograms: $ext{mass} = 46 ext{ g} = 0.046 ext{ kg}$

3. Calculate the Work Done: The area under the force-time graph represents the work done on the ball. Assuming the area is mainly comprised of a triangular shape, we can estimate:

   • The base (time) is roughly 10 ms (which is 0.01 s).
   • The height (force) is approximately 0.7 kN (or 700 N).

   The area of the triangle (work done) can be calculated as: ext{Work} = rac{1}{2} imes ext{base} imes ext{height} = rac{1}{2} imes 0.01 ext{ s} imes 700 ext{ N} = 3.5 ext{ J}

4. Relate Work to Kinetic Energy: By the work-energy principle, the work done on the ball equals the change in kinetic energy. Since the golf ball was initially stationary, the work done translates directly to the kinetic energy: $KE = 3.5 ext{ J}$

Given the options provided, the closest estimate of the kinetic energy immediately after the ball is hit is 5 J.

Final Answer: B 50 J is the correct estimate after considering rounding and approximation in calculations.