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Check the correctness of the formula S =...

Check the correctness of the formula `S = ut + 1/3 "at"^2` where S is the distance , u is velocity , a is acceleration and t is time.

Text Solution

Verified by Experts

Dimensionally, `LHS=[L]`
`RHS=[LT^(-1)][T]+[LT^(-2)][T]^(2)=[L]+[L]`
Since, the dimension of each term on both sides are same, the equation is correct dimensionally, However, we cannot say anything about the physical correctness of the formula . in fact, we know that the correct formula is `S=ut+1/2at^(2)`
Hence, we conslude that dimensional correctness is no guarantee for physical correctness of the formula. however, dimensional incorrectness guarantees the physical incorrectness of the fomula. Inspite to the above limitation, the method is still helpful to a great extent.
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