Revision as of 14:43, 12 October 2008

Outcomes

• Students should be able to label pairs of forces in a range of situations
• Students should understand that the forces are acting on different objects and therefore do not cancel out!!

Specification References

• none

Starter

• Two students on skateboards pushing off each other
• Tug of war with Newton scales

Main Body of Lesson

• Students are to make their own forcemeter using acetate sheets and steel springs. They are to use the W = m g formula from 3-TAS-01 and mark the scale on their forcemeter with set weights.
• They can test their forcemeters by measuring the weight of unknown objects A,B and C

Newton's Third Law Powerpoint including demos:

• Use of force plate on data studio of student jumping
• Stationary trolley with bow and rubber arrow
• Releasing a balloon attached to a tight string across the room
• Getting out of a row boat
• Earth pulls on apple and therefore apple pulls up on Earth

Plenary

• Firing a water rocket from Broadfield

Homework

This homework sheet has a few questions that requires the pupils to examine their knowledge of Newton's third law. Her are the answers.

Additional Information

Resources Required

• Skateboards x 2
• Force plate on data studio
• Trolley with bow and arrow mounted on top
• Balloon attached to taunt string with straw
• Tug of war with force meters
• Large crate on front desk
• Globe and apple

Textbook References

• None

Website References

• None

Skills Addressed

• Obtaining

Safety/Hazards

The most dangerous aspects of this lesson are the tug-of-war and using the skate boards. For both demonstrations, please make sure that there is more than enough room, minimising the chance that a pupil could fall over band their head. Please refer to manual handling risk assessment, particularly if you are getting pupils to throw a medicine ball to each other.

Notes

• None