MHB Work energy principle and power

AI Thread Summary
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.
Shah 72
MHB
Messages
274
Reaction score
0
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
 
Mathematics news on Phys.org
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!
 

Thread 'Trigonometry problem of interest'

Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
View full post »
Thread 'Imaginary Pythagoras'

Thread 'Imaginary Pythagoras'

I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...
View full post »

Thread 'Fermat's Last Theorem'

Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
View full post »

Similar threads

MHB Calculate the Length & Potential Energy of a Sliding Box on a Ramp
Replies
9
Views
2K
MHB The work energy principle and power
Replies
2
Views
1K
MHB Work energy principle and power
Replies
1
Views
1K
MHB Work energy principle and power
Replies
1
Views
873
MHB Work energy principle and power
Replies
16
Views
2K
MHB Work energy principle and power
Replies
3
Views
2K
MHB Work energy principle and power
Replies
8
Views
2K
MHB Work energy principle and power
Replies
4
Views
1K
MHB Work energy principle and power
Replies
9
Views
1K
B Conservation of Energy: Ball on a U-Shaped Ramp
Replies
2
Views
402

Hot Threads

Recent Insights

Back
Top