Question

On a new scale of temperature (which is linear) and called the W scale, the freezing and boiling points of water are 39°W and 239°W respectively. What will be the temperature on the new scale, corresponding to a temperature of 39°C on the Celsius scale ?

• A. ${200}^{o}W$
• B. ${139}^{o}W$
• C. ${78}^{o}W$
• D. ${117}^{o}W$

Answer 1

Answer: (D)

Given,

$T_f={39}^{0}W$

$T_b={230}^{0}W$

We know that,

$\frac{T_b-T_f}{{100}^{0}C-0^{0}C}=\frac{T-{39}^{0}C}{{39}^{0}C}$

$\frac{239-39}{100}=\frac{T-39}{39}$

$\frac{200}{100}=\frac{T-39}{39}$

$T-39=2\times 39={78}^{0}W$

$T=39+78={117}^{0}W$

The correct option is D.