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Question
If the unit of force is 100 N, unit of length is 10 m and unit of time is 100 s, what is the unit of mass in this system of units?
Solution
Dimension of force F = `[MLT^-2]` = 100 N ......(i)
Length (L) = `[L]` = 10 m ......(ii)
Time (t) = `[T]` = 100 s ......(iii)
Substituting values of L and T from equations (ii) and (iii) in equation (i), we get
M × 10 × (100)–2 = 100
⇒ `(M xx 10)/(100 xx 100)` = 100
⇒ M = 100 × 1000 kg
M = 105 kg
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