3Force-3

Outcomes

• Pupils can arrange all the GCSE quantities into two groups: scalars and vectors.
• Pupils appreciate that force is a vector quantity and understand the nature of this.
• Pupils can name and label forces on stationary objects using arrows (1-D) and show that they are balanced.
• Pupils can add force vectors that act along a line.

Specification References

• 1.10 distinguish between vector and scalar quantities
• 1.11 appreciate the vector nature of a force
• 1.12 add forces that act along a line

Starter

• Thumbs up-Thumbs down; pupils all stand up, you read out a quantitiy and they put thumbs up if it's a scalar and down if its a vector. If they get it wrong they have to sit down. You can help avoid sheep mentality by getting them to clse their eyes
• Write "1) A car travels at a constant speed" and "2) A car travels at a changing velocity". Ask them to discuss with the person next to them how both statemnt can be applied to the same car.

Main Body of Lesson

• Explain that force vectors are depicted as arrows to show the direction, with the length of the arrow representing the magnitude of the force. You could introduce the 'head' and 'tail' of the force vector.
• Also introduce the idea that the resultant of two given forces is an imaginary force and is equivalent to the actual forces. It would have the same effect as the real forces combined.
• Go through the examples on how to add vectors from the power point slide. Emphasis how to add vectors 'head to tail'. Make them redraw the arrows in 'head to tail' formation.
• The powerpoint does go into perpendicular vectors, with some real life examples (this is a bit beyond the syllabus and can be skipped over if there is little time or the group is struggling with vectors in 1-D.

Plenary

In preparation for the next lesson give out the force table sheet and ask pupils to find the resultant forces and predict which way the block will move and how quickly it will more. This will be tested in the following lesson.

Homework

• Homework sheet in folder
• Students could also research the difference between speed and velocity and how the change in velocity can occur by the velocity only changing direction and not magnitude. This could lead them to the idea of circular motion.

Textbook References

• None

Website References

• None

Safety/Hazards

• None

Notes

• None