d. Frictional force is not always helpful. Give the reason for this.
Answers
Explanation:
Frictional force causes a lot of losses in general upkeep and wear and the tearing of machinery. But almost all crucial tasks cannot be carried out without the presence of friction. Basic activities like walking and writing on a surface are possible due to friction. Hence it is considered as a necessary evil.
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Answer:
it has disadvantages
Explanation:
Friction produces a lot of heat in various parts of the machinery and this leads to wastage of energy as heat.
Opposes motion, hence more energy is needed to overcome friction.
Noise production in machines is irritating as well as leads to energy loss.
) Friction Slow Down motion. 2) it reduces the efficiency of machine . 3) it produces heat which may damage machines. 4) it wears out steps of staircase in buildings and foot over bridges.
While running a machine, energy is lost because of friction. Hence, in this case, friction is a disadvantage.
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