Author Question: What length of a certain metal wire of diameter 0.15 mm is needed for the wire to have a resistance ... (Read 740 times)

cagreen833 · **on:** Jul 29, 2018

What length of a certain metal wire of diameter 0.15 mm is needed for the wire to have a resistance of 15 ? The resistivity of this metal is 1.68 10-8 m.

A) 16 mm
B) 16 cm
C) 1.6 m
D) 16 m
E) 160 m

Question 2

You want to confine an electron in a box (an infinite well) so that its ground state energy is 5.0 10-18 J.

What should be the length of the box? (h = 6.626 10-34 J s, mel = 9.11 10-31 kg)
A) 0.11 nm
B) 0.22 nm
C) 0.15 nm
D) 0.18 nm