- #1
Jiman
- 28
- 6
I feel that force is also function of time.
A body is a collection of particles.Jiman said:This is only true for particle but not for extensive body?
Thank you so much!PeroK said:A body is a collection of particles.
Jiman said:I feel that force is also function of time.
ZapperZ said:I am sure that you are citing this out of context, which is a nasty thing to do to any author. You should at least make an effort at (i) citing the exact phrase that led you to conclude this and (ii) citing the location of the source, i.e. where in the book did you get this.
Force can be defined as the gradient of the potential energy field, i.e.
F = -∇U
By that alone, I can claim that force depends only on position, since it is a function of the gradient (i.e. d/dx) of the potential energy field.
So how is that not correct in this context?
Thank you for reminding me. I'll correct it.
Zz.
Jiman said:Thank you for reminding me. I'll correct it.
Sorry, English is not my native language. I hardly use English in my life. But I can understand what you're replying to.ZapperZ said:You need to learn how to communicate in a clearer manner here. In the 4 posts that you have made in this thread, all of them were one-sentence responses. In this post alone, I've typed more than what you had written, combined!
It is difficult to know what it is really that you are going to "correct". Furthermore, I don't see any indication that you've understood the answer that you were given, since you did not indicate that one way or another.
If you wish that members responding to your questions provide detailed and thoughtful answers, you should at least put in the same level of effort in your questions and posts.
Zz.
PF is tolerable for this. It is one of the reasons I like itJiman said:Sorry, English is not my native language.
Kleppner said:"At first glance there seems to be no problem in finding the motion
of a particle if we know the force. Newton’s second law tells us the acceleration,
which we can integrate to find the velocity, and we can then
integrate the velocity to find the position. This sounds simple but there
is a problem: to carry out these calculations we need to know the force
as a function of time, but force is usually known as a function of position
as, for example, the spring force or the gravitational force. The
problem is serious because physicists are generally interested in interactions
between systems, which means knowing how the force varies with
position, not how it varies with time."
The concept of time and force is the relationship between the passage of time and the application of force. Time is a measure of how long an event or action takes, while force is a measure of the strength or energy used to cause an object to move or change its state.
Time and force are closely related, as the amount of force applied to an object can affect how long it takes for that object to move or change. For example, a greater force will cause an object to move faster, while a smaller force will take longer to produce the same effect.
There are many examples of time and force in our daily lives. For instance, when we push a door open, we are applying force over a period of time to move the door. When a car accelerates, the force of the engine is acting over time to increase its speed. Even something as simple as throwing a ball involves the force of our arm acting over a period of time to propel the ball forward.
Understanding time and force is crucial in many fields of science and engineering. It allows us to accurately predict how objects will move and change over time, and helps us design and build structures and machines that can withstand different forces. It also plays a key role in fields such as physics, mechanics, and astronomy.
There are various ways to measure time and force, depending on the specific situation. Time can be measured using clocks, watches, or other devices that track the passage of time. Force can be measured using instruments such as spring scales, force gauges, or strain gauges. In more complex situations, advanced techniques such as motion capture and force plates may be used to measure time and force simultaneously.