A pair of eyeglass frames are made of an epoxy plastic (coefficient of linear expansion = 122 ✕ 10-6 °C-1). At room temperature (20.0°C) the frames have circular lens holes 2.00 cm in radius. To what temperature must the frames be heated if lenses 2.01 cm in radius are to be inserted into them?

The new temperature is  

Explanation:

From the question we are told that

   The coefficient of linear expansion is  

    The temperature is  

    The radius of the frames is

    The new radius is  

The change in radius is mathematically represented as

substituting values

The increase in radius can also be mathematically represented as

Where is the the new temperature , making it the subject we have

substituting value  

increase masses, decrease separation