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प्रश्न
The mass of an aluminum rod varies directly with its length. If a 16 cm long rod has a mass of 192 g, find the length of the rod whose mass is 105 g.
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उत्तर
According to the question, the mass (m) of an aluminium rod varies directly with its length (l).
Here, we use the direct proportion.
In diret proportion, `m/l = k` ...(Constant)
∴ `m/l = 192/16 = 12`
⇒ k = 12
If mass of the rod = 105 g
Then, `m/l = k`
⇒ `105/l = 12`
⇒ `l = 105/12 = 8.75 cm`
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