I need to find the coefficient of the kinetic friction of the following:
"a block weighing 300 newtons is moved at a constant speed over a horizontal surface be a force of 50 newtons applied parallel to the surface"
would I do the following?
k = coefficient of kinetic friction
since k = f/n
k = 50/300 = .166667?
it just seems too simple? am I doing something wrong?
No. You are correct! :)
Just because something seems too simple, doesn't mean you did something wrong. Be more confident in yourself!
To find the coefficient of kinetic friction (k), you need to use the formula:
k = f / N
Where:
- f is the force of kinetic friction
- N is the normal force acting on the block
In this case, the normal force is equal to the weight of the block, which is 300 newtons.
The force applied parallel to the surface is a force of 50 newtons.
Since the problem states that the block is moved at a constant speed, it means that the applied force (50 N) is equal to the force of kinetic friction. Therefore, you can determine the coefficient of kinetic friction as:
k = 50 N / 300 N = 0.1667
So, you have calculated the correct value for the coefficient of kinetic friction. It is indeed approximately 0.1667.
You're on the right track! To find the coefficient of kinetic friction (k), you need to use the equation you mentioned: k = f/n, where f is the force of kinetic friction and n is the normal force.
In this case, the force applied parallel to the surface (f) is given as 50 newtons. However, note that this force is not the force of kinetic friction itself. The block is moved at a constant speed, which means the force of kinetic friction must be equal in magnitude and opposite in direction to the applied force. Therefore, the force of kinetic friction is also 50 newtons.
To find the normal force (n), you need to consider that the block is on a horizontal surface. The normal force is the force exerted by the surface perpendicular to the block, which balances out the weight of the block. Since the block is on a horizontal surface and moves at a constant speed, the normal force is equal in magnitude to the weight of the block.
You mentioned that the block weighs 300 newtons, so the normal force is also 300 newtons.
Now you can calculate the coefficient of kinetic friction (k):
k = f/n = 50/300
k = 0.166667
So your initial calculation is correct. The coefficient of kinetic friction for this scenario is approximately 0.166667. Remember to round your answer to an appropriate number of significant figures!