W=dke=dpe potential energy

In summary, the body will move 2m in the direction of the force, and there must be a change in potential energy associated with the force. The change of the body’s potential energy associated with the force is:(a) zero,(b) +10 J,(c) -10 J, (d) infinite.
  • #1
yolo123
63
0
A conservative force of 5 N causes a body to move 2 m in the direction of the force. The change of the body’s potential energy associated with the force is:
(a) zero,
(b) +10 J,
(c) -10 J, (d) infinite.

Let's say the force is pushing the body for 2m, there must be a change in KE. But, for change of KE, there must be change in PE.
I don't understand this. Can you explain to me how W=DKE=DPE?
 
Physics news on Phys.org
  • #2
yolo123 said:
A conservative force of 5 N causes a body to move 2 m in the direction of the force. The change of the body’s potential energy associated with the force is:
(a) zero,
(b) +10 J,
(c) -10 J, (d) infinite.

Let's say the force is pushing the body for 2m, there must be a change in KE. But, for change of KE, there must be change in PE.
I don't understand this. Can you explain to me how W=DKE=DPE?
you might want to consider both the work energy theorem and the conservation of energy theorem to show the relationship between work done by a conservative force and the PE change.
 
  • #3
I think I found the answer: -10J. Say it is gravity, object goes down two meters, -10J of DPE.
 
  • #4
yolo123 said:
I think I found the answer: -10J. Say it is gravity, object goes down two meters, -10J of DPE.
Yes that is correct.
You should satisfy yourself (with no other non conservative forces doing work ) that the KE change is ?
 
  • #5
yolo123 said:
Can you explain to me how W=DKE=DPE?

It is not. Look up the definition of potential energy. There is a minus sign there.
 
  • #6
10j!
 
  • #7
I did not say that your previous answer is wrong.

Is the work positive or negative?
 
  • #8
Nasu, I was answering PhantomJay's question! The change in KE= +10J
 
  • #9
yolo123 said:
Nasu, I was answering PhantomJay's question! The change in KE= +10J


yolo123 said:
Nasu, I was answering PhantomJay's question! The change in KE= +10J
Correct. So you originally stated that that Wc=dKE=dPE.
Do you wish to correct that statement, for the special case as in your example when only conservative forces are doing work?
 

1. What is the formula for potential energy?

The formula for potential energy is W = dke + dpe, where W represents the total potential energy, dke represents the change in kinetic energy, and dpe represents the change in potential energy.

2. What does the 'd' in the formula stand for?

The 'd' in the formula represents change in a variable. In this case, it represents the change in kinetic and potential energy.

3. How is potential energy different from kinetic energy?

Potential energy is the energy that an object possesses due to its position or configuration, while kinetic energy is the energy an object possesses due to its motion. In other words, potential energy is stored energy, while kinetic energy is energy in motion.

4. What is the unit of measurement for potential energy?

The unit of measurement for potential energy is joules (J). Other commonly used units include calories (cal) and kilowatt-hours (kWh).

5. Can potential energy be negative?

Yes, potential energy can be negative depending on the reference point chosen. If the reference point is set at the ground level, potential energy of an object above the ground will be positive, while potential energy of an object below the ground will be negative. However, the total potential energy (W) will always be positive.

Similar threads

  • Introductory Physics Homework Help
Replies
15
Views
300
  • Introductory Physics Homework Help
Replies
5
Views
738
  • Introductory Physics Homework Help
Replies
14
Views
968
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
751
  • Introductory Physics Homework Help
Replies
7
Views
954
  • Introductory Physics Homework Help
Replies
23
Views
286
  • Introductory Physics Homework Help
Replies
20
Views
2K
  • Introductory Physics Homework Help
Replies
11
Views
1K
  • Introductory Physics Homework Help
Replies
15
Views
260
Back
Top