Recent content by indoguy427

Since the contact-surface system is doing positive work, then don't we still get a negative change in internal energy?

hm there's a gap in my understanding with regards to the first law / internal vs. external forces... can you please explain how an internal force relates to the first law vs. an external force acting on the system?

hmm - if i consider the contact surface, i still don't see how it will change things...

Homework Statement I am trying to understand how the process of friction heating a block as it slides can be explained by the first law of thermodynamics. Homework Equations W_net(net work on object) = change in KE change in internal energy = Q(heat added to system) - W_by (work...

Homework Statement I am trying to understand a concept that pops up in my hwk problems about friction, specifically static friction. In an example in my book, it shows that when you turn a car around a corner, you have 3 forces: normal, gravity (these cancel and are in the vertical...

hmm what I am not understanding here is where static friction is coming into play, both for walking and driving...can someone explain how it comes into play and how in the driving case it provides the centripetal force?

Hey Guys, This is my first time posting ... sooo here it goes! I have spent the past hour trying to figure out how we walk (in a physics sense) - I can't seem to find anything good on google that really answers my question. I have a general idea that when i put my foot down, I push...