Why do tyres have a rippled surface and not a plane surface ?
Because a rippled surface is beautiful to look at.
Because the force of friction is more between a rippled surface and the ground than between a plane surface and the ground.
Because the force of friction is less between a rippled surface and the ground than between a plane surface and the ground.
It is done to reduce the chances of puncturing of the tyre.
When two bodies are rubbed against each other beat is produced. Where from the heat energy comes ?
The mechanical work done in rubbing the bodies is transformed into the heat energy,
When two bodies are rubbed, their molecules are set in violent motion. Due to this motion, some of the heat energy of the bodies comes to their surface.
When the two bodies are rubbed, some of the adhesive force between the two bodies is transformed into kinetic energy.
None of these.
Which of ihe following is fungi ?
All of these.
Which of the following statements is false about fossils ?
Fossils help us to know the age of earth.
Fossils are remains of plants and animal life which become hardened like stone during the course of ages by the pressure of upper layers.
Fossils help us know about plants and animals of p ' re-historic periods.
None of these.
Why a dog runs during summer, with tongue out of his mouth ?
Because dog feels thirsty.
Because he wants to expose his tongue to the rays of'sun. This disinfects the dog's mouth.
Because the dog feels cooi due to evaporation from tongue.
Because during summer", dog begins to breath through his, mouth.
Which of the following birds can fly ?
None of these.
In how many hours Earth completes, one rotation about its own axis ?
3651 x 24 hrs.
What is a thermopile ?
It is a sensitive instrument used for detecting and measuring thermal radiation.
It is an instrument used for measuring the heat content of a given system.
It is a pile of thermometers.
It is an instrument which supplies thermoelectric current.
Why water is used as a cooler in engine radiators ?
Because water is cheap and easily available.
Because water is a bad conductor of electricity.
Because water has high specific heat and absorbs heat quickly.
Because water is a good conductor of heat.
What is the average density of earth ?
1. World Geography -Test-01
2. World Geography -Test-02
3. World Geography -Test-03
4. Geography of India -Test-01
5. Geography of India -Test-02
6. Geography of India -Test-03
7. Geography of India -Test-04
8. Geography of India -Test-05
9. History of India - Test - 01
10. History of India - Test - 02
11. History of India - Test - 03
12. History of India - Test - 04
13. History of India - Test - 05
14. History of India - Test - 06
15. History of India - Test - 07
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