Give reasons
? Sparks are produced when a pair of scissors is sharpened against a grinding wheel
? A piece o chalk wears out asit is used on a black board.
?Wet surfaces are more slippery
?Power is applied to a caromboard
?A man walking on a street slips a banana skin.
?Oil is applied to the moving part of a machine...
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QUES 1. Sparks are produced when a pair of scissors is sharpened against a grinding wheel ?
ANS 1.Grinding is the process in which the pieces of metal from the edge of the knife fall out and due to high temperature on account of friction between two surfaces small pieces will heat up and start to glow, producing sparks.
Hence due to the force of friction , sparks are produced when a pair of scissors is sharpened against a grinding wheel.
QUES 2. Why a piece of chalk wears out as it is used on a black board ?
ANS 2. a piece of chalk wears out as it is used on a blackboard because it's molecules are used up while writing on the blackboard.
QUES 3. Why wet surfaces are more slippery ?
ANS 3. Wet surface has water in between the surface and legs of a person. Water decreases forces of interaction between surface and legs, hence LESS FRICTION is caused. ... The wet surfaces are more slippery because, when some water or a liquid is spread on the floor, the roughness of the floor is decreased at that instance.
QUES 4. Why powder is applied to a caromboard ?
ANS 4. when powder is sprinkled on carrom board it acts as an lubricant and reduces friction and hence helps in smooth movement of the coins.
QUES 5. Why a man walking on a street slips a banana skin ?
ANS 5. Banana peel has a smooth surface thus, when one steps a foot on the banana peel, the friction between the feet and ground is decreased and friction between the peel and ground is also decreased as the surface is smooth. This leads to slip of the leg and the man then falls down.
QUES 6. Why oil is applied to the moving part of a machine ?
ANS 6. The moving part of machine has always the problem of damaging because of the friction.So in these parts oil is usually appliedto lessen the friction.So themachine will work properly.
hope it helps
pls mark it as the brainliest answer :)
ANS 1.Grinding is the process in which the pieces of metal from the edge of the knife fall out and due to high temperature on account of friction between two surfaces small pieces will heat up and start to glow, producing sparks.
Hence due to the force of friction , sparks are produced when a pair of scissors is sharpened against a grinding wheel.
QUES 2. Why a piece of chalk wears out as it is used on a black board ?
ANS 2. a piece of chalk wears out as it is used on a blackboard because it's molecules are used up while writing on the blackboard.
QUES 3. Why wet surfaces are more slippery ?
ANS 3. Wet surface has water in between the surface and legs of a person. Water decreases forces of interaction between surface and legs, hence LESS FRICTION is caused. ... The wet surfaces are more slippery because, when some water or a liquid is spread on the floor, the roughness of the floor is decreased at that instance.
QUES 4. Why powder is applied to a caromboard ?
ANS 4. when powder is sprinkled on carrom board it acts as an lubricant and reduces friction and hence helps in smooth movement of the coins.
QUES 5. Why a man walking on a street slips a banana skin ?
ANS 5. Banana peel has a smooth surface thus, when one steps a foot on the banana peel, the friction between the feet and ground is decreased and friction between the peel and ground is also decreased as the surface is smooth. This leads to slip of the leg and the man then falls down.
QUES 6. Why oil is applied to the moving part of a machine ?
ANS 6. The moving part of machine has always the problem of damaging because of the friction.So in these parts oil is usually appliedto lessen the friction.So themachine will work properly.
hope it helps
pls mark it as the brainliest answer :)
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