The kinetic energy of an electron accelerated in an x-ray tube is 94.5 keV. Assuming it is nonrelativistic, what is its wavelength? Take the mass of an electron to be 9.11 x 10-31 kg. 0.00388 pm

An electron initially at rest is accelerated across a potential difference of 8 kV. What are its wavelength, momentum, kinetic energy, and total energy? 13.8 90.68 8 518 pm ✔ keV/c keV (kinetic) XkeV (total)

A ball has a mass of 0.129 kg just before it strikes the Earth after being dropped from a building 36.2 m tall. What is its de Broglie wavelength? The acceleration of gravity is 9.8 m/s 2 and Planck’s constant is 6.62607 × 10−34 J · s. Answer in units of m.

What is the velocity (in m/s) of a 0.430 kg billiard ball if its wavelength is 7.70 cm (large enough for it to interfere with other billiard balls)?

= 1. Photoelectric effect. In a photoelectric experiment in which monochromatic light of wave- length \ falls on a potassium surface, it is found that the stopping potential Vstop is 1.9 V for > 300 nm and 0.88 V for \ = 400 nm. Imagine we know neither Planck's constant, nor the workfunction for potassium, nor the threshold frequency fo. But assume we do know the elementary charge e 1.60 × 10-19 C and want to test the theoretical prediction of Eintsein's theory. = (a) From the given data, calculate a value for Planck's constant, h. (b) From the same data, find the workfunction Eo and the threshold frequency fo for potas- sium. (c) Then compare your results for h and Eo to their known values (see Knight, Table 38.1 for the work function). (d) Plot eVstop as a linear function of frequency f. Include the information you have found in parts (a) and (b) as well as the experimental data.

During a certain experiment, the de Broglie wavelength of an electron is 610 nm = 6.1 x 10- m, which is the same as the wavelength of orange light. How fast (in m/s) is the electron moving? m/s