1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
castortr0y [4]
3 years ago
14

An electron with kinetic energy 2.9 keV moving along the positive direction of an x axis enters a region in which a uniform elec

tric field of magnitude 7.5 kV/m is in the negative direction of the y axis. A uniform magnetic field is to be set up to keep the electron moving along the xaxis, and the direction of the field is to be chosen to minimize the required magnitude of the field. What is the magnitude of the magnetic field in mT?
Physics
1 answer:
Vladimir79 [104]3 years ago
3 0

The electric force on the electron is opposite in direction to the electric field E. E points in the -y direction, so the electric force will point in the +y direction. The magnitude of the electric force is given by:

F = Eq

F = electric force, E = electric field strength, q = electron charge

We need to set up a magnetic field such that the magnetic force on the electron balances out the electric force. Since the electric force points in the +y direction, we need the magnetic force to point in the -y direction. Using the  reversed right hand rule, the magnetic field must point in the -z direction for this to happen. Since the direction is perpendicular to the +x direction of the electron's velocity, the magnetic force is given by:

F = qvB

F = magnetic force, q = charge, v = velocity, B = magnetic field strength

The electric force must equal the magnetic force.

Eq = qvB

Do some algebra to isolate B:

E = vB

B = E/v

Let's solve for the electron's velocity. Its kinetic energy is given by:

KE = 0.5mv²

KE = kinetic energy, m = mass, v = velocity

Given values:

KE = 2.9keV = 4.6×10⁻¹⁶J

m = 9.1×10⁻³¹kg

Plug in and solve for v:

4.6×10⁻¹⁶ = 0.5(9.1×10⁻³¹)v²

v = 3.2×10⁷m/s

B = E/v

Given values:

E = 7500V/m

v = 3.2×10⁷m/s

Plug in and solve for B:

B = 7500/3.2×10⁷

B = 0.00023T

B = 0.23mT

You might be interested in
A basket has a mass of 5.5 kg. Find the magnitude of the normal force if the basket is at rest on a ramp inclined above the hori
storchak [24]
Here is the correct answer of the given problem above.
Given that the basket has a mass of 5.5kg, the magnitude of the normal force if the basket is at rest on a ramp inclined above the horizontal is at 12 degrees. The solution is simple: 
<span>Fn at rest = lmgl </span>
<span>= 5.5kg (9.80N/kg) 
=</span><span> mgCos12degrees 
Hope this answer helps. </span>
8 0
3 years ago
Read 2 more answers
1. An excited lithium atom emits a red light with wavelength a = 671nm. What is the corresponding photon energy? hc (6.63 x 10-3
Rudiy27

Answer:

 E = 2,964 10⁻¹⁹ J

Explanation:

The energy of the photons is given by the Planck relation

          E = h f

the speed of light is related to wavelength and frequency

          c = λ f

we substitute

          E = h c /λ

let's reduce the magnitude to the SI system

          λ = 671 nm = 671 10⁻⁹ m

let's calculate

          E = 6.63 10⁻³⁴ 3 10⁸ /671 10⁻⁹

          E = 2,964 10⁻¹⁹ J

6 0
3 years ago
If your body is dehydrated, the control center in the brain will stimulate the release of a hormone which causes the reabsorptio
Yanka [14]

Answer:

It is an example of negative feedback mechanism

Explanation:

Negative feedback mechanism is the process by which the output of a system, process or mechanism is fed back into the input in order to reduce the error in the system.

In the system described in this question, the reabsorption of water is the output, a feedback signal is sent to the control center, which is the input in order to control the release of the hormone responsible for reabsorption of water into the blood.

7 0
3 years ago
Need help will mark you the Brainliest
Hatshy [7]
The last one is correct (D)
8 0
2 years ago
The linear momentum of a truck of mass 5000 kg that is moving at a velocity of +30 m/a is ___ kg m/s
miv72 [106K]

Linear momentum of a truck is 1,50,000 kg.m/s

Explanation:

Linear momentum is the product of the mass and velocity of an object. It is a vector quantity, which have a magnitude and a direction.

Linear momentum is a property of an object which is in motion with respect to a reference point (i.e. any object changing its position with respect to the reference point).

It's SI units are kg.m/s

Linear momentum is a vector quantity.

Linear momentum formula (p) = mass × velocity

Given data mass = 5000 kg ; velocity = 30 m/s

P = 5000 × 30

Linear momentum p= 1,50,000 kg.m/s

7 0
3 years ago
Other questions:
  • A 5.5kg mass is pushed with a force of 31N across a table having μk of 0.350. Find how fast it will accelerate, taking friction
    9·1 answer
  • Which is belief held by sociologists who work from a social-conflict perspective
    10·2 answers
  • A container has a mass of 1.293 metric tons. what is the mass of the container in grams
    13·2 answers
  • An object is located 50.0 cm from a convex mirror. the focal length is 25.0 cm. what is the image distance? Use the equation di=
    13·2 answers
  • What are 3 wether instuerments i know anemometer and barometer but the third one and what there job!!
    8·1 answer
  • Two waves with equal amplitude meet each other, resulting in a wave zero amplitude. Which phenomenon explains this result?
    14·2 answers
  • The resultant of two vectors acting at a 90°-angle can be determined from the _____ of the rectangle.
    12·2 answers
  • Please I need help........
    9·2 answers
  • What is the frequency of a wave that has a wavelength of 20 cm and a speed of 10 m/s
    8·1 answer
  • Calculate the magnetic field and its direction at point P, which is 2.0 cm away from the top wire and 4.0 cm from the bottom wir
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!