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Question
Answer the following in short.
Explain the various functions that a machine can perform.
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Solution
Various functions that a machine can perform are :
- Changing the direction of applied force − Example: When a flag is hoisted with the help of a pulley.
- Changing the magnitude of applied force − Example: Bottle opener multiplies the applied force and much less effort is required to open the cap.
- Applying force at a convenient point − Example: hi a pair of scissors, the input force is applied at the handle of the scissors which cuts the paper at the other end of the blade.
- Changing the speed of an object − Example: While riding a bicycle, force is applied on pedals which multiplies the speed.
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RELATED QUESTIONS
A pulley system with VR = 4 is used to lift a load of 175 kgf through a vertical height of 15 m. The effort required is 50 kgf in the downward direction. (g = 10 N kg-1)
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