When a forward bias is applied to a p-n junction, it(a) raises the potential barrier.(b) reduces the majority carrier current to zero.(c) lowers the potential barrier.(d) None of the above.

A valence electron in a crystal absorbs a photon of wavelength, =0.300nm . This is just enough energy to allow the electron to jump from the valence band to the conduction band. What is the size of the energy gap?

At saturation, when nearly all the atoms have their magnetic moments aligned, the magnetic field is equal to the permeability constant 0 multiplied by the magnetic moment per unit volume. In a sample of iron, where the number density of atoms is approximately 8.50 1028 atoms/m3, the magnetic field can reach 2.00 T. If each electron contributes a magnetic moment of 9.27 10-24 A m2 (1 Bohr magneton), how many electrons per atom contribute to the saturated Held of iron?

Check Your Understanding Verify that /V and e0/d have the same physical units.

The Hall effect is demonstrated in the laboratory. A thin rectangular strip of semiconductor with width 5 cm and cross-sectional area 2 mm" is attached to a battery and immersed in a field perpendicular to its surface. The Hall voltage reads 12.5 V and the measured drift velocity is 50 m. s. What is the magnetic field?

The Hall effect is to be used to find the sign of charge carries in a semiconductor sample. The probe is placed between Own poles of a magnet so that magnetic field Is pointed up. A current is passed through a rectangular sample placed horizizontally. As current is passed through the sample in the east direction, the north side of the sample is found to be at a higher potential than the south side. Decide if the number density of charge carriers is positively or negatively charged.

At what temperature, in terms of Tc, is the critical field of a superconductor one-half its value at T = 0 K?

Determine the current generated in a superconducting ring of niobium metal 2.00 cm in diameter when a 0.020 0-T magnetic field directed perpendicular to the ring is suddenly decreased to zero. The inductance of the ring is 3.10 × 10−8 H.

Check Your Understanding What conditions are necessary for superconductivity?

The collector current of a transistor is 3.4 A for a base current of 4.2 mA. What is the current gain?