Kinetic Energy/Work Problem

  • Thread starter crimsonn
  • Start date
  • Tags
    Kinetic
In summary, the problem is to use the work energy theorem to find the force needed to accelerate an electron with a mass of 9.11 X10^-31 kg from a speed of 1.50 X10^7 m/s to an unknown speed in a distance of 0.0125 meters. There is confusion about the initial and final speeds and the unit of distance used in the problem.
  • #1
crimsonn
30
0

Homework Statement



use the work energy theorem to find the force required to accelerate an electron (m=9.11 X10^-31 kg) from a speed of 1.50 X10^7 m/s in a distance of .0125

Homework Equations


W=Fd KE= 1/2mv^2

W=KE


The Attempt at a Solution



I've tried this problem about eight times, and each time I managed to get a different answer, but this is my try at a solution

W=Fx
W/x= F

W=1/2mv^2

mv^2/2x = F

however, this does not work for me.

the answer is 3.56 X10 -19N
 
Physics news on Phys.org
  • #2
crimsonn said:

Homework Statement



use the work energy theorem to find the force required to accelerate an electron (m=9.11 X10^-31 kg) from a speed of 1.50 X10^7 m/s in a distance of .0125

[...]

To a speed of what? What is the unit of distance?
 
  • #3
Yeah, was this electron at rest to begin with, or was it in motion already? Check the wording of your question.
 

1. What is kinetic energy?

Kinetic energy is the energy an object possesses due to its motion. It is a scalar quantity, meaning it has magnitude but no direction.

2. How is kinetic energy calculated?

Kinetic energy is calculated using the formula KE = 1/2 * mv^2, where m is the mass of the object and v is its velocity.

3. What is the relationship between kinetic energy and work?

Kinetic energy and work are closely related, as work is defined as the transfer of energy through a force acting over a distance. In other words, when a force is applied to an object and causes it to move, work is done on the object and its kinetic energy increases.

4. Can kinetic energy be converted into other forms of energy?

Yes, kinetic energy can be converted into other forms of energy, such as potential energy or thermal energy. For example, when a moving object hits a stationary object, its kinetic energy is converted into sound and heat energy.

5. How does the mass and velocity of an object affect its kinetic energy?

The kinetic energy of an object increases with both its mass and velocity. As the mass of an object increases, its kinetic energy increases at a proportional rate. However, the kinetic energy increases at a much greater rate with an increase in velocity, as it is squared in the kinetic energy formula.

Similar threads

  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
903
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
2
Replies
56
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
762
  • Introductory Physics Homework Help
Replies
19
Views
2K
  • Introductory Physics Homework Help
Replies
11
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
Back
Top