Please use the template and include any standard equations you may have been taught that appear relevant.Caleb S said:The problem is asking me to find the final speed of a 1100 kg car traveling at 24 m/s through 18m of mud, where the resistive force on the car is 17000 N.
I don't actually know how to go about doing this, so any pointers in the right direction would be super helpful.
There's no template included.haruspex said:Please use the template and include any standard equations you may have been taught that appear relevant.
See item 2 at https://www.physicsforums.com/threads/guidelines-for-students-and-helpers.686781/Caleb S said:There's no template included.
You mean kinetics. Kinematics is something else.Caleb S said:Kinematics equations
Right. So what can you say about the change in KE in passing through the mud?Caleb S said:Work = m*a*x
Kinetic Energy = .5*m*v^2
There is a standard template provided by this forum for posting homework questions. My understanding is that it appears automatically when you create a thread, which implies you deleted it.Caleb S said:There is no template for the problem. It is given to me in a text form.
One of the equations you posted in post #4 expresses work done in terms of a force and a distance.Caleb S said:I just don't see how the resistive force of friction relates to the final velocity.
Right - that is an example of the m.a.x equation you posted earlier, since F=m.a.Caleb S said:Oh wait I just realized that there is an equation for the work done by friction: W = -F*d
And from there you could calculate the final velocity by running it back through the kinetic energy formula, right?Caleb S said:I think so... it would be something along the lines of KE - Wf = KEnet, correct?
Kinematics is correct. See this wikipedia article: https://en.wikipedia.org/wiki/Kinematicsharuspex said:You mean kinetics. Kinematics is something else.
Kinematics is a branch of classical mechanics that describes the motion of points, bodies (objects), and systems of bodies (groups of objects) without considering the forces that caused the motion.
That's why this problem is kinetics (it concerns masses and forces), not kinematics.Mark44 said:Kinematics is correct. See this wikipedia article: https://en.wikipedia.org/wiki/Kinematics
From the linked article:
Yes.Caleb S said:I think so... it would be something along the lines of KE - Wf = KEnet, correct?
I stand corrected.haruspex said:That's why this problem is kinetics (it concerns masses and forces), not kinematics.
The equation for calculating final speed with work and friction is v = √(2μmgd + v02), where μ is the coefficient of friction, m is the mass of the object, g is the acceleration due to gravity, d is the distance traveled, and v0 is the initial velocity.
Friction acts as a resistive force, meaning it opposes the motion of an object. As a result, it reduces the final speed of an object by dissipating some of the energy that is being used to do work on the object.
Yes, it is possible for the final speed of an object to be greater than its initial speed if the object is being pushed or pulled by a force that is greater than the force of friction acting on it. In this case, the work done by the external force will be greater than the work done by friction, resulting in an increase in speed.
Work is a measure of the energy transferred to an object to make it move. In the equation for calculating final speed with friction, the term 2μmgd represents the work done by friction on the object. This work is then subtracted from the initial kinetic energy (v02) to determine the final speed of the object.
The coefficient of friction is a measure of the amount of friction between two surfaces. A higher coefficient of friction means that there is more resistance to motion, resulting in a lower final speed. Conversely, a lower coefficient of friction means there is less resistance to motion, resulting in a higher final speed.