How Is the Speed of a Sled Calculated at the Top of a Hill?

AI Thread Summary
To calculate the speed of a sled at the top of a hill, start by analyzing the forces acting on the sled and drawing a free body diagram. Use the work-energy principle, applying the equations for work, potential energy, and kinetic energy. Determine the acceleration of the sled based on the net force and then calculate the final velocity using the distance traveled and acceleration. The answer is known to be 4.29 m/s, but the focus is on understanding the process rather than just obtaining the result. Additionally, a question about calculating change in internal energy based on moles and temperature change was raised, indicating a broader interest in thermodynamic principles.
linnus
Messages
22
Reaction score
0

Homework Statement



You are pulling your sister on a sled to the top of a 17.0 m high, frictionless hill with a 10.0° incline. Your sister and the sled have a total mass of 50.0 kg. You pull the sled, starting from rest, with a constant force of 127 N at an angle of 45.0° to the hill. If you pull from the bottom to the top, what will the speed of the sled be when you reach the top?

Homework Equations


W=F*x (cos (angel))
PE=mgh
KE=1/2mv^2



The Attempt at a Solution

 
Physics news on Phys.org
Do you have any work to show?
 
You'll first need to figure out what the acceleration will be.

Then you can solve for v using this equation:

a(x-x_0)=\frac{1}{2}(v^2-v_0^2)
 
I'm not looking for an answer here. I know the answer, it is 4.29 m/s
But can someone give me a step by step process on how to get that answer?
Thanks
 
linnus said:
I'm not looking for an answer here. I know the answer, it is 4.29 m/s
But can someone give me a step by step process on how to get that answer?
Thanks

I'm sorry but that is not what we do here. The homework helpers HELP with homework. We do not give away solutions, which is essentially what you are asking for. If you would like we can help you figure out how to the correct answer, but you'll have to show some independent thought on the problem first. I'll get you started with some questions:

You posted three relevant equations. Why did you decide to post those? How are they useful here?
 
linnus said:
I'm not looking for an answer here. I know the answer, it is 4.29 m/s
But can someone give me a step by step process on how to get that answer?
Thanks

Step 1: draw a free body diagram of the scene.
Step 2: Determine the forces acting on the object.
Step 3: Find the acceleration of the object.
Step 4: Find the velocity of the object based on distance and acceleration.
 
Quick question:

How do you calculate the change in internal energy given only the number of moles, and the temperature change?
 
Back
Top