- #1
lekh2003
Gold Member
- 538
- 342
I've just been thinking, and I don't know why I couldn't figure this out on my own, but I got this question bugging me.
I was moving a sofa the other day. The sofa was against a wall. I started thinking why it was harder to push the sofa parallel to the wall when it was touching the wall rather then when it was not touching the wall. I hope you see what I mean.
My initial thought was that there was friction against the wall, but then I thought mathematically. What would the friction be? I am not exerting any force on the sofa pushing it towards the wall, so why is there friction?
Why is it harder to push an object when it is simply in contact with the wall, even though there is no force to act on the object to generate friction?
I was moving a sofa the other day. The sofa was against a wall. I started thinking why it was harder to push the sofa parallel to the wall when it was touching the wall rather then when it was not touching the wall. I hope you see what I mean.
My initial thought was that there was friction against the wall, but then I thought mathematically. What would the friction be? I am not exerting any force on the sofa pushing it towards the wall, so why is there friction?
Why is it harder to push an object when it is simply in contact with the wall, even though there is no force to act on the object to generate friction?