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Why is red light used as danger signal?...

Why is red light used as danger signal?

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UNITED BOOK HOUSE-QUESTION PAPER 2017-EXERCISE
  1. Under what condition will the object and image always be on the same ...

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  2. An image of size 1/n times the object size is formed in a convex mirro...

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  3. Why is red light used as danger signal?

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  4. Explain by using graph the minimum angle of deviation of a ray of ligh...

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  5. Production of X-rays and emissions of electron in photoelectric effect...

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  6. Find the energy required by an electron to have its de Broglie wavelen...

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  7. State the features of photoelectric effect

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  8. In a magnetic field the curvature of the path of a beta- particle is g...

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  9. What will be the wavelength of the light emitted due to a transition o...

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  10. Which kind of nuclear reaction produces energy in a nuclear reactor...

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  11. In a nuclear decay, a nucleus emits one alpha-particle and then two be...

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  12. If two inputs of a NAND gate are joined, what type of a gate is formed...

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  13. State one difference between n-type and p-type semiconductors.

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  14. In a transistor emitter-base junction is always forward biased while t...

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  15. Show that equivalent resistance in parallel combination is always less...

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  16. How can the sensitivity of a potentimeter be increased ?

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  17. A Potentiometer has 10 wires each of 1 metre length and the total resi...

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  18. Draw a graph representing the change in specific resistance with tempe...

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  19. Find the equivalent resistance between the two ends A and B of the fol...

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  20. Define lost volt,State the factors on which the internal resistance of...

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