Find velocity of hanging block in a pulley system

AI Thread Summary
To find the velocity of the hanging block in the pulley system, apply the law of conservation of energy, considering both kinetic energy (KE) and gravitational potential energy (Ug). The work done by friction must also be accounted for, which is determined by the coefficient of kinetic friction and the normal force on the block on the desk. The equation Wother = ΔKE + ΔUg + ΔUel indicates that the total work done by the system equals the change in kinetic energy plus the change in gravitational potential energy. It is not necessary to solve for each mass separately; instead, focus on the overall energy changes in the system. The final velocity can be calculated after accounting for the energy lost to friction.
Twiggy92
Messages
4
Reaction score
0
A pulley is set up on the edge of a desk. A light string connects a 10 kg block laying on the desk to a 4 kg block hanging off the pulley. The only significant friction is with the desk, and the coefficient of kinetic friction is 0.20. Use the law of conservation of energy to find the speed of the system after the hanging block has dropped 1.5 m.



Wother = ΔKE + ΔUg + ΔUel
KE = 0.5 * m * v2
Ug = m*g*y



in both KE and Ug equations I need to use mass. Do I solve these equations for each of the masses and then add them all together to equal Wother?
 
Physics news on Phys.org
You only need to solve the first equation, W is the work done by friction, and the system would gain kinetic energy but lose gravitational potential energy.
 

Thread 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'A bead-mass oscillatory system problem'

Thread 'A bead-mass oscillatory system problem'

I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
View full post »

Similar threads

Pulley system problem: 6 Pulleys and 1 Mass
Replies
5
Views
934
Newton's Second Law (Pulley Sustem)
Replies
3
Views
2K
Time period of SHM & Energy conservation in pulley-spring-block system
Replies
24
Views
3K
Force applied on the pulley of a system
Replies
8
Views
3K
How Do You Calculate the Angular Motion of a Pulley System?
Replies
15
Views
2K
Block-pulley system and kinetic energy
Replies
1
Views
3K
Mass and pulley system (Rotational Dynamics)
Replies
9
Views
2K
Acceleration of a block on a massive pulley
Replies
1
Views
2K
A system comprising blocks, a light frictionless pulley, and
Replies
6
Views
4K
Finding the period of pulley system
Replies
22
Views
3K

Hot Threads

Recent Insights

Back
Top