Problem 3 The electrons in the beam of a television tube have an energy of 6 keV

Question

Problem 3 The electrons in the beam of a television tube have an energy of 6 keV. The tube is oriented so that the electrons move horizontally from north to south. The vertical component of the Earth's magnetic field at the location of the television has a magnitude of 45.0 pT and is pointing down. a) In which direction does the force on the electrons act (enter N for north, S for South, E for East, or W for West) Neglect a possible horizontal component of the magnetic field You are correct. Computer's answer now shown above. Your receipt is 163-415 To b) What is the magnitude of the acceleration due to the vertical component of the Earth's magnetic field of an electron in the beam? Remember Newton's second Law? Suemit Answer Incorrect. Tries 4/6 Previous Tries c) If the inclination of the earth's magnetic field near the TV is 80deg,calculate the magnitude of the force on the electrons due to the horizontal component of the Earth's magnetic field. Submit Answer Tries 06

Explanation / Answer

a) West

b) let v is the speed of the electron.

we know, KE = (1/2)*m*v^2

==> v = sqrt(2*KE/m)

= sqrt(2*6*10^3*1.6*10^-19/(9.1*10^-31))

= 4.59*10^7 m/s

Force acting on elctron, F = q*v*B*sin(90)

m*a = q*v*B

a = q*v*B/m

= 1.6*10^-19*4.59*10^7*45*10^-6/(9.1*10^-31)

= 3.63*10^14 m/s^2

c) magnetic force due to the horizontal component of magnetic field,

F = q*v*Bx*sin(180) (here Bx and v are anti parellel)

= 0

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.