GCSE Physics (AQA)

346 videos | 23 hours

Kinetic Energy

Please subscribe to watch this video.

This, and all other videos, are included in our premium subscriptions.

Premium accounts get access to all videos.

Forces Work done and energy transfer

Kinetic Energy

3:49 Work, Kinetic Energy and Gravitaitonal Potential Energy
Spec 4.1.1.1 4.1.1.2 4.5.2
Previous Work & Displacement Next Kinetic & GPE Conversions
  • Kinetic energy is the energy stored in a moving object.
  • Examples include a running hare and a falling apple, both of which gain kinetic energy through movement.
  • Kinetic energy (KE) is calculated based on an object's mass and speed, using the formula KE = 0.5 * m * v^2, where:
  • m = mass in kilograms
  • v = speed in meters per second
  • KE = kinetic energy in joules
  • Direction of movement does not affect kinetic energy, hence speed is used in the formula instead of velocity.
  • The formula for kinetic energy is provided in exams, but students need to know how to rearrange and apply it.
  • Example problem: Calculate the speed of a 0.2 kg cricket ball given 200 joules of kinetic energy.
  • Rearrange the kinetic energy formula to isolate v^2 (v^2 = 2KE/m).
  • Take the square root of both sides to solve for v.
  • Substitute values into the rearranged formula to find v = sqrt(2 * 200 / 0.2) = 44.7213 m/s.
  • Round the calculated speed to two significant figures, resulting in 45 m/s.

Please subscribe to access these revision notes.

This, and all other video notes, are included in our premium subscriptions.

Premium accounts get access to all videos and revision notes.