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Check dimensional consistency of given e...

Check dimensional consistency of given equation.

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For example
`x=x_(0)=v_(0)t+(1)/(2)at^(2)`
Here, x is distance covered by object in time t.
`x_(0)`= initial position of object during motion
x= final position
`v_(0)`= initial velocity
a= acceleration
`LHS=x=M^(0)L^(1)T^(0)`
In RHS tere are three terms,
`x_(0)=M^(0)L^(1)T^(0)`
`v_(0)t=[L^(1)T^(-1)T^(1)]=M^(0)L^(1)T^(0)`
In `(1)/(2)at^(2)` is constant term which is dimensionless.
`:.at^(2)=[M^(0)L^(1)T^(-2)][T^(2)]`
`=M^(0)L^(1)T^(0)`
Here all terms in given equation have same dimension. Hence, given equation,
`x=x_(0)+v_(0)t+(1)/(2)at^(2)` is dimensionally consistence. (Dimensionally valid).
Test of consistency of dimension tells us no more no less than test of consistency of units. If equation fails consistency test it is proved wrong, but if it passes it is not proved right Thus, a dimensionally correct equation need not be actually an exact (correct) equation but al dimensionally wrong (incorrect) equation must be wrong.
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KUMAR PRAKASHAN-UNITS AND MEASUREMENT-SECTION -A (QUESTIONS- ANSWERS)
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  2. Write a note on combination of error.

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  3. Explain error of a sum or a difference.

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  4. Write rule for error in result due to multiplication and division

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  5. What is significant number? What is significant digit?

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  6. Write and explain rules of determining significant digit with example.

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  7. Write rules of "Round off" numbers.

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  8. Explain : "By using significant digit we can prevent unnecessary long ...

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  9. What points to be considered during addition.

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  10. What points to be considered during multiplication and division of sig...

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  11. Explain uncertainty or error in given asurement by suitable example.

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  12. What is dimension of a physical quantity ?

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  13. Define dimensional formula and dimensional equation by using sultable ...

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  14. What is dimensional analysis ?

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  15. Obtain the relation between the units of some physical quantity in two...

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  16. Obtain the relation between the MKS and CGS unit of work.

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  17. Write principle of Homogeneity of dimension.

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  18. Check dimensional consistency of given equation.

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  19. Heat produced in a current carrying conducting wire depends on current...

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  20. Write limitation of dimensional analysis.

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