Question

MUST Answer Part A, B and C

A) Calculate the rate of heat flow transferred through an aluminum bar that is 25 square cm in cross section and 30 cm long. The thermal conductivity of the aluminum bar is ?? = 205 ??/(?? ? ??). The temperature at the hot end is 100°F while at the cold end is 20°F

B) Blue light of wavelength 485 nm falls on a silicon photocell made from a semiconductor with bandgap is 1.35 eV. What is the maximum fraction of the light’s energy that can be converted into electrical power?

C) Find the maximum wavelength of the photon needed to cause an electron to jump from the valence to the conduction band in (aa) cadmium selenide, band gap of 1.73 eV; (ab) cadmium sulfide, band gap 2.42 eV

Answer 1