Kinetic Energy

• What is kinetic energy?

  Energy stored in moving objects
• Why does a stationary object have no kinetic energy?

  Because it is not moving
• How do you calculate kinetic energy?

  Using the equation $KE =$$0.5 \times m \times v^2$
• What is the unit of speed in the kinetic energy equation?

  meters per second (m/s)
• What is the kinetic energy of a car with a mass of 700 kg moving at 20 m/s?

  140,000 Joules
• How do scientists convert Joules into kilojoules?

  By dividing by 1,000
• What is the kinetic energy of a cyclist and bike with a total mass of 100 kg moving at 15 m/s?

  11,250 Joules
• What is the kinetic energy of the cyclist and bike in kilojoules?

  11.25 kJ
• How do you calculate the mass of a tennis ball with a kinetic energy of 75 Joules traveling at 50 m/s?

  Using $m =$$\frac{KE}{0.5 \times v^2}$
• What is the mass of the tennis ball if its kinetic energy is 75 Joules and speed is 50 m/s?

  0.06 kg
• What are the energy changes in a car running on petrol?

  • Chemical energy stored in petrol
  • Converted to kinetic energy in the engine
  • Powers the car's movement
• What is the formula for kinetic energy?

  • $KE =$$0.5 \times m \times v^2$
  • Where:
  • $KE$ = kinetic energy in Joules
  • $m$ = mass in kilograms
  • $v$ = speed in meters per second