4- An electron in an x-ray machine is accelerated through a potential difference of 5*104 V before it hits the target. The change in electric potential energy is: (e = 1.6*10-19 C)a) -8*10-15 Jb) 8*10-15 Jc) 5*10-13Jd) 9*10-12J 5- A proton is released from rest at the origin in a uniform electric field in the positive x direction with magnitude 3000 N/C. The change in the electric potential energy of the proton–field system when the proton travels to x =5 m is: (e = 1.6*10-19 C)a) 24*10-16Jb) -24*10-16 Jc) 5000 Jd) 1000 J

What is the potential 0.530 x 10-10 m from a proton (the average distance between the proton and electron in a hydrogen atom)?

Integrated Concepts A lightning bolt strikes a tree, moving 20.0 C of charge through a potential difference of 1.00102 MV. (a) What energy was dissipated? (b) What mass of water could be raised from 15°C to the boiling point and then boiled by this energy? (c) Discuss the damage that could be caused to the tree by the expansion of the boiling steam.

An electron is to be accelerated in a uniform electric field having a strength of 2.00106 V/m. (a) What energy in keV is given to the electron if it is accelerated through 0.400 m? (b) Over what distance would it have to be accelerated to increase its energy by 50.0 GeV?

A constant electric field accelerates a proton from rest through a distance of 2.00 m to a speed of 1.50 105 m/s. (a) Find the change in the protons kinetic energy. (b) Find the change in the systems electric potential energy. (c) Calculate the magnitude of the electric field.

A simple and common technique for accelerating electrons is shown in Figure 7.46, where there is a uniform electric field between two plates. Electrons are released, usually from a hot filament, near the negative plate, and there is a small hole in the positive plate that allows the electrons to continue moving, (a) Calculate the acceleration of the electron if the field strength is 2.50104 N/C . (b) Explain why the electron will not be pulled back to the positive plate once it moves through the hole. Figure 7.46 Parallel conducting plates with opposite charges on them create a relatively uniform electric field used to accelerate electrons to the right. Those that go through the hole can be used to make a TV or computer screen glow or to produce X- rays.

Cathode ray tubes (CRTs) used in old-style televisions have been replaced by modern LCD and LED screens. Part of the CRT included a set of accelerating plates separated by a distance of about 1.50 cm. If the potential difference across the plates was 25.0 kV, find the magnitude of the electric field in the region between the plates.

In nuclear fission. a nucleus splits roughly in half. (a) What is the potential 2.00 10-14 m from a fragment that has 46 protons in it? (b) What is the potential energy in MeV of a similarly charged fragment at this distance?

An evacuated tube uses an accelerating voltage of 40 kV to accelerate electrons to hit a copper plate and produce x rays. Non-relativistically, what would be the maximum speed of these electrons?

In the classical model of a hydrogen atom, an electron orbits a proton with a kinetic energy of +13.6 eV and an electric potential energy of 27.2 eV. (a) Use the kinetic energy to calculate the classical orbital speed. (b) Use the electric potential energy to calculate the classical orbital radius.