Question 1: Define kinetic energy in your own words.

Answer: Kinetic energy is the energy an object has due to its motion.

Question 2: Explain how the mass and velocity of an object affect its kinetic energy.

Answer: Kinetic energy increases with greater mass and higher velocity; specifically, it is proportional to both.

Question 3: What is the formula used to calculate kinetic energy?

Answer: Kinetic Energy = 0.5 × mass × velocity²

Question 1: A sprinter with a mass of 70 kg reaches a velocity of 10 m/s. Calculate her kinetic energy.

Answer: Kinetic Energy = 0.5 × 70 kg × (10 m/s)² = 3500 Joules

Question 2: A football (soccer ball) with a mass of 0.43 kg is kicked at a velocity of 15 m/s. What is its kinetic energy?

Answer: Kinetic Energy = 0.5 × 0.43 kg × (15 m/s)² = 48.375 Joules

Question 1: Describe an experiment to measure the kinetic energy of a rolling ball in a sports science lab. Include the variables you would control and safety precautions.

Answer: An experiment could involve rolling a ball down an inclined plane and measuring its velocity at the bottom using sensors. Variables to control include the mass of the ball, the angle of incline, and surface friction. Safety precautions include wearing safety goggles, ensuring the area is clear of obstacles, and handling equipment carefully.

Question 1: A cyclist weighing 75 kg accelerates from 0 to 20 m/s in 10 seconds. Describe how the cyclist's kinetic energy changes during this acceleration.

Answer: The cyclist's kinetic energy increases from 0 to 0.5 × 75 kg × (20 m/s)² = 15,000 Joules as they accelerate.

Question 2: If the cyclist's velocity doubles, how does their kinetic energy change? Explain your reasoning.

Answer: The kinetic energy increases by a factor of four because kinetic energy is proportional to the square of velocity.

Question 1: A basketball with a mass of 0.6 kg is thrown with a velocity of 8 m/s. Calculate its kinetic energy. Show all steps.

Answer: Kinetic Energy = 0.5 × 0.6 kg × (8 m/s)² = 19.2 Joules

Question 2: Explain how understanding kinetic energy can help improve safety in sports activities like football or hockey.

Answer: Understanding kinetic energy helps in designing safer equipment and playing techniques by reducing high-impact collisions. For example, athletes can learn to control their speed and impact to prevent injuries, and equipment can be made to absorb energy effectively.

Question 1: Describe how kinetic energy is considered in the design of sports helmets to protect athletes.

Answer: Helmets are designed to absorb and dissipate the kinetic energy from impacts, reducing the force transferred to the athlete's head and preventing injuries.

Question 2: Explain how understanding kinetic energy can influence the development of sports equipment such as balls and bats.

Answer: Knowledge of kinetic energy helps in choosing materials and designing shapes that optimize energy transfer, improve performance, and reduce injury risks.