Look at the activities listed below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
• Suma is swimming in a pond.
• A donkey is carrying a load on its back.
• A wind-mill is lifting water from a well.
• A green plant is carrying out photosynthesis.
• An engine is pulling a train.
• Food grains are getting dried in the sun.
• A sailboat is moving due to wind energy

Question

Look at the activities listed below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
• Suma is swimming in a pond.
• A donkey is carrying a load on its back.
• A wind-mill is lifting water from a well.
• A green plant is carrying out photosynthesis.
• An engine is pulling a train.
• Food grains are getting dried in the sun.
• A sailboat is moving due to wind energy

Infinity Learn · Accepted Answer

Suma is swimming in a pond. Work is done because the displacement of swimmer takes place and a force is applied.A donkey is carrying a load on its back. Donkey is not doing any work in carrying the load as weight (acting vertically downward) and displacement (acting horizontal) are perpendicular to each other. A wind-mill is lifting water from a well. Work is done because the displacement of water takes place and wind mill does a work against gravity.A green plant is carrying out photosynthesis. No work is done, because no displacement takes place. An engine is pulling a train. Work is done because the displacement of train takes place and a force is applied by the engine. Food grains are getting dried in the sun. No work is done because displacement does not take place. A sailboat is moving due to wind energy. Work is done because the displacement of sailboat takes place and a force is applied by the wind.

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