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Question
What is a lever?
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Solution
A lever is a special case of the application of the law of moments. It is a rigid bar, straight or bent, which is capable of rotation about a fixed point or a fixed-line, called the axis of rotation. This fixed point or the axis of rotation is called the fulcrum. An effort E is applied at point A of the lever to overcome resistance (or load) at another point B, as shown in the diagram.
RELATED QUESTIONS
Which class of lever will always have MA > 1 and why?
Draw a diagram of a lever which is always used as a force multiplier. How is the effort arm related to the load arm in such a lever?
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What class of lever is it? Give one more example of the same class of lever.
The diagram shows the use of a lever.
- State the principle of moments as applied to the above lever.
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A lever is used to multiply the force.
