Confusing System of Masses Question

  • Thread starter Thread starter Keeo
  • Start date Start date
  • Tags Tags
    Confusing System
AI Thread Summary
The discussion focuses on calculating the maximum horizontal force that can be applied to a lower wooden block without causing an upper block to slip. The coefficients of static and kinetic friction between the blocks and the table are provided. Participants suggest starting with the friction force equation, emphasizing the importance of determining which block will slip first. A calculation example is given, illustrating how to find the friction force acting on the lower block. The conversation concludes with the original poster expressing gratitude for the guidance received.
Keeo
Messages
2
Reaction score
0
May somebody please help me on this question, I have no idea even where to begin.

A 0.5kg wooden block is placed on top of a 1.0kg wooden block. The coefficient of static friction between the two blocks is 0.35. The coefficient of kinetic friction between the lower block and the level table is 0.20. What is the maximum horizontal force that can be applied to the lower block without the upper block slipping?
 
Physics news on Phys.org
Welcome to PF!

Hi Keeo! Welcome to PF! :smile:

Hint: which will slip first, the upper block relative to the lower block, or the lower block relative to the table?

What is the maximum possible friction force between the upper block and the lower block? :smile:
 
Ok, I think I can help get you started on this one. For ease I'm calling the 1kg block m1 and the .5kg block m2. First think I would do is consider the equation fs= us*N where fs is the force of friction, us is the coefficient of friction and N is the normal force on the block. So, for m1 you would do this: .2*(9.8*1kg) which would then give you 1.96 N as your fs1. Hint: This is in the opposite direction of the applied force. See if that can help start you out and then go from there.
 
Thanks for all of your help it has actually lead me to an answer. Also thank you for welcoming me here.:biggrin:
 
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 .
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...
Back
Top