answer the following 1

1. Define physics.
2. How do the practical applications help mankind?
3. what are  physical quantities?give examples.
4. How are the physical quantities or the relation explained?
5. What is dimensional equation?
6. What is error?
7. What is approximation?
8. What is one light year?
9. What is one astronomical Unit?
10. What is Laser pulse method?
11. What is percentage error?
12. Explain principle of homogeneity?
13. Give the formula for surface tension of a liquid.
14. Explain the time period of the simple pendulum.

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