Up Work Done Power Kinetic Energy GPE Momentum I Momentum II

 

                                                

 

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Energy & Momentum

 

 

 

Momentum and energy.

 

 

 

This module covers work on kinetic and potential energy in the context of falling objects and projectiles, as well as looking at changes of momentum for objects undergoing collisions.  These ideas are then applied to analyse and understand safety features in vehicles.

 

 

Details of the content and teaching order can be seen below.

 

 

 

Lesson

Learning Outcomes

Notes

1 - Work done

  • Know that Energy is transferred when forces act on moving objects.

  • Be able to select and use the equation:

W = F x d

 

2 - Power

 

• Know that power is a measure of the rate at which energy is transferred.

• Be able to solve numerical problems involving energy and power using the equation

Power = work done ś time taken

or Power = energy transferred ś time taken

 

3 - Kinetic energy

  • Select and use the equation:

Ek = œ x m x vČ

 

For Higher tier classes - calculations of GPE and KE, including rearranging to find velocity for a falling object.

Foundation classes can still cover the ideas qualitatively - Catapult practical is straightforward and reasonably entertaining.

4 - Gravitational potential energy

  • Select and use the equation:

Ep = m x g x h

 

For Higher tier classes - calculations of GPE and KE, including rearranging to find velocity for a falling object.

Foundation classes can still cover the ideas qualitatively - Catapult practical is straightforward and reasonably entertaining.

5 - Momentum I

 

• Know that all massive objects have momentum when in motion.

• Be able to calculate the momentum of a moving object using the formula p = m Ś v

• Be able to find the change in momentum of an object, given information about its velocity.

 
 

5 - Momentum II

• Know that momentum is conserved in a closed system.

• Be able to apply the law of conservation of momentum to determine the outcome of collision or explosion events.

 

7

Physics of transport

 

  • Understand the physics behind airbags and crumple zones.

  • Discuss the reasons for speed limits and speed cameras.

 

 

discuss crumple zones and airbags in terms of time taken to come to rest increasing which reduces average force, and also in terms of work done over a larger distance - again reducing average force.