A tungsten wire is used to determine the melting point of indium.The resistance of the tungsten wire is 3.000 W at 20 $\degree$C and increases to 4.850 W as the indium starts to melt.a_tungsten = 4.50 x 10^-3 ( $\degree$C)^-1.What is the melting temperature of indium? A)132 $\degree$C B)157 $\degree$C C)351 $\degree$C D)731 $\degree$C

Question

Quizplus · Accepted Answer

We can use the formula R = Ro(1 + αΔT) for the resistance of the wire, where R is the final resistance, Ro is the initial resistance (3.000 W), α is the temperature coefficient of resistance for tungsten (4.50 x 10^-3 / °C) and ΔT is the change in temperature.

We can rearrange the formula to ΔT = (R/Ro - 1) / α and plug in the values:

ΔT = (4.850/3.000 - 1) / (4.50 x 10^-3) = 157 °C

Therefore, the melting point of indium is 20°C + 157°C = 177°C = 351°F.

The answer is B, 157°F.

A Tungsten Wire Is Used to Determine the Melting Point °\degree°

A Tungsten Wire Is Used to Determine the Melting Point $\degree$