Posted by Physics on Wednesday, March 18, 2009 at 7:58pm.
A 15 N wooden block is dragged for 15 meters across a wooden floor in 15 seconds...
I'm given that the mew (the greek leter uk) or however u say it is .2
I have to make a free body diagram
I sloved and got
Fn = 15 N
mg = 15 N
Ff = 3 N
How do I solve for the force applied to get the force opposite Ff. It has to be greater than 3 N sense the block moved across the floor but how do I know the net force? I need to know the force applied which I don't know and have to solve for and don't know how to...
The quetion then asks me how much work was performed and covert to horsepower which i think I can do once I have the net force but I don't know how to get the net force without the force applied. I'm given no angle or anthing at which the force was applied either...

Physics  bobpursley, Wednesday, March 18, 2009 at 8:03pm
If it was dragged at constant velocity, then you are right with Ff=3N (note, not negative). Net force is the accelerating force, above the friction force. If it were at constant velocity, you have no idea what net force is. With constant veloicty, net force is zero (it is not accelerating).
Work performed: Ff*distance 
Physics  Basic Trig, Wednesday, March 18, 2009 at 8:19pm
how do I solve for accelerating force above friction force?