Question
Why don't we have interference when two candles are placed close to each other and the intensity is seen at a distant screen? What happens if the candles are replaced by laser sources?
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Answer
In order to get interference, the sources should be coherent, i.e. they should emit wave of the same frequency and a stable phase difference. Two candles that are placed close to each other are distinct and cannot be considered as coherent sources. Two independent sources cannot be coherent. So, two different laser sources will also not serve the purpose.
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- Boltzmann constant has value of:
- 1.38 × 10 - 23 joule per Kelvin.
- 1.38 × 10 - 28 joule per Kelvin.
- 1.38 × 10 - 30 joule per Kelvin.
- None of these.
- SI unit of Boltzmann constant is given by:
- Joules per meter
- Joules per Kelvin
- Joules per Newton
- None of these
- According to kinetic theory give formula for pressure of idea gas.
- According to kinetic theory what is average kinetic energy of molecules of ideal gas?
- What is law of equipartition of energy?
Read the case study given below and answer any four subparts:
Potential energy is the energy stored within an object, due to the object's position, arrangement or state. Potential energy is one of the two main forms of energy, along with kinetic energy. Potential energy depends on the force acting on the two objects.
→Potential energy is the energy stored within an object, due to the object's position, arrangement or state. Potential energy is one of the two main forms of energy, along with kinetic energy. Potential energy depends on the force acting on the two objects.
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- potential energy
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- Kgm/s
- Kgm/s2
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- None of these
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- Vector quantity
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