Two cylinders P and Q of equal mass are made from the same metal. If the radius of P is n times the radius of Q , then calculate ratio of their resistances.

Explanation

To solve the problem of finding the ratio of the resistances of two cylinders P and Q made from the same metal and having equal mass, we can follow these steps:

### Step 1: Understand the relationship between mass, volume, and density
Since both cylinders are made from the same metal, they have the same density (ρ). The mass (m) of each cylinder can be expressed in terms of its volume (V) and density:
\[ m = \rho V \]
Thus, for both cylinders:
\[ V_P = V_Q \]

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