MHB Work energy principle and power

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The discussion revolves around calculating the speed of a box sliding down a ramp using the work-energy principle. The height of the ramp is 20 cm, and the box starts from rest, allowing for the application of conservation of energy. The gravitational potential energy (GPE) at the top is converted into kinetic energy (KE) at the bottom, leading to the equation 1/2mv^2 = mgh. By substituting the values for g and h, the mass cancels out, simplifying the calculation. The final speed of the box at the bottom of the ramp is determined to be 2 m/s.
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A box slides down a smooth ramp. The height of the ramp is 20cm and the length of the ramp is 2.5m. The box starts from rest. What is the speed of the box when it reaches the bottom of the ramp?
I don't understand how to solve this. Pls help
 
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We can apply conservation of energy.

What is the energy due to gravity at the beginning?
What is the kinetic energy at the end?
 
Increase in KE= loss of GPE
1/2mv^2= mgh
So gpe at the top = m×10× 0.2
GPE at the bottom = 0J
 
Klaas van Aarsen said:
We can apply conservation of energy.

What is the energy due to gravity at the beginning?
What is the kinetic energy at the end?
I don't understand how to solve this. Pls help
 
You have the correct equation.
Fill in g and h.
And we can cancel m from both sides.
 
Klaas van Aarsen said:
You have the correct equation.
Fill in g and h.
And we can cancel m from both sides.
h=0.2m, so v= 2m/s. I was getting confused with the length of the ramp.
Thanks a lottt!
 
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