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Unit summary

Check your knowledge and understanding

1. Asan and Alina attempt to balance on a plank 4. Calculate the moment of a 6 N force if the
of wood placed over a log. How far should each shortest distance between the pivot and the line
sit from the fulcrum if Asan has a greater mass of force action is 175 cm.
I can … textbooks nis edu kz
than Alina?
5. At a distance of 10 cm from the pivot, there are
2. A boy grips an item in a vice in the school 4 suspended masses of 100 g each. What force
workshop. He holds the vice handle not in the should be applied at a distance of 20 cm for the
middle, but at the end. Why? lever to be in equilibrium?

3. Why are scissors with long blades and short
handles used to cut paper, while scissors with
long handles and short blades are used to
cut metal?

Assess your learning
Reflect on how well you met the learning objectives of this unit. Use the worksheet provided by
your teachers to develop your own targets.

How confident am I?

experimentally determine the position of the centre of mass of a plane (of regular and irregular shapes)

explain the concept of turning force and give examples from daily life
determine the efficiency of an inclined plane experimentally and in problem-solving

evaluate the use of simple mechanisms and formulate a ‘golden rule of mechanics’
formulate and solve problems related to the moment of force principle for a body in equilibrium

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