Author Question: A metal surface has a work function of 1.50 eV. Calculate the maximum kinetic energy, in eV, of ... (Read 80 times)

joe · **on:** Jul 29, 2018

A metal surface has a work function of 1.50 eV. Calculate the maximum kinetic energy, in eV, of electrons ejected from this surface by electromagnetic radiation of wavelength 311 nm.

(c = 3.00 108 m/s, h = 6.626 10-34 J s, e = - 1.60 10-19 C, 1 eV = 1.60 10-19 J)

Question 2

A conducting bar slides without friction on two parallel horizontal rails that are 50 cm apart and connected by a wire at one end. The resistance of the bar and the rails is constant and equal to 0.10 .

A uniform magnetic field is perpendicular to the plane of the rails. A 0.080-N force parallel to the rails is required to keep the bar moving at a constant speed of 0.50 m/s. What is the magnitude of the magnetic field? A) 0.10 T
B) 0.25 T
C) 0.36 T
D) 0.54 T
E) 0.93 T