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What factors affect the kinetic energy of a moving object?

What factors affect the kinetic energy of a moving object?. What is kinetic energy?. Mawada on Thursday morning. Mawada ’s crazy cat. The word ‘kinetic’ comes from the Greek word ‘kinesis’, meaning motion. Kinetic energy is the energy an object has because it is moving .

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What factors affect the kinetic energy of a moving object?

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  1. What factors affect the kinetic energy of a moving object?

  2. What is kinetic energy? Mawadaon Thursday morning Mawada’scrazy cat The word ‘kinetic’ comes from the Greek word ‘kinesis’, meaning motion. Kinetic energy is the energy an object has because it is moving. All moving things have kinetic energy, but the amount of energythey have is not just dependent on how fastthey are moving.

  3. KE = ½ x mass x velocity2 = ½mv2 How is kinetic energy calculated? The kinetic energy (KE) of an object can be calculated using this equation: • Mass is measured in kilograms (kg). • Velocity is measured in metres per second (m/s). • KE is measured in joules (j).

  4. Calculating kinetic energy group question A car with a mass of 1,500kg travels at a velocity of 20m/s. What is the kinetic energy of the car? kinetic energy = ½ xmass x velocity2 = ½ x 1,500kg x 20 m/s 2 = 300,000J = 300kJ

  5. KE = ½mv2 Ö 2KE m 2KE v2 v = m = Rearranging the KE equation Sometimes it is necessary to rearrange the kinetic energy equation in order to calculate the mass or the velocity of a moving object. What are the rearranged versions of this equation for calculating mass and velocity?

  6. Ö 2KE mass velocity = Ö 2 x 2,250,000J 20,000kg = Calculating velocity group question A lorry has a mass of 20,000kg. If its kinetic energy is 2.25mJ, at what velocity is it travelling? KE = ½ xmass x velocity2 = 15m/s

  7. The kinetic energy of cars

  8. 1,000kg 2,000kg 20km/h 40km/h Dangerous speeding? Use the KE = ½mv2 equation to fill in the kinetic energy values in the table below for two cars each travelling at two different velocities. KE = 15.46kJ KE = 30.91 kJ KE = 61.72 kJ KE = 123.4 kJ What factor – mass or velocity – has the greatest effect on the kinetic energy of a moving object?

  9. Too much kinetic energy Doubling the mass of a moving object doubles its kinetic energy, but doubling the velocity quadruples its kinetic energy. If the velocity of a car is slightly above the speed limit, its kinetic energy is much greater than it would be at the speed limit. This means that: • It is more difficult to stop the car and there is more chance of an accident. • If the car does collide with something, more energy will be transferred, causing more damage.

  10. Tasks for the rest of the lesson • Carry out the practical on the back of your worksheet • Try the GPE and KE practice questions How cool is this!!

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