Q73 of 106 Page 310

The mass of an aluminium 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.

According to the question, the mass(m) of an aluminium rod varies directly with its length(l). Here, we use the direct proportion.


In direct proportion,


∴


⇒ k = 12


If mass of the rod = 105g


Then,


⇒


⇒ cm


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