How to calcoulate force applied?

AI Thread Summary
To calculate the force required to roll a 30 kg metal block across the floor at uniform speed with a coefficient of friction of 0.16, the frictional force must be overcome. The weight of the block is 294 N, and the normal force is also 294 N, resulting in a frictional force of 47.04 N. Since uniform speed indicates zero acceleration, the applied force must equal the frictional force to maintain motion. Therefore, the force applied is 47.04 N. Work done can be calculated using the formula Work = force * distance.
jamesblim168
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Homework Statement


if the coefficient of friction between a 30 kg metal block and the floor is 0.16, what force is required to roll this block across the floor at a uniform speed? how much work is done? find : weight of force, normal force, force applied and fricitional force

Homework Equations


fn=mg
Ff=UxFn

The Attempt at a Solution

so far i only got this
weight of force = 294
normal force =294
frictional force = 47.04

How do i get force applied?
 
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Uniform speed implies zero acceleration. Have you drawn a free body diagram?
What does 'weight of force' mean? Given your numbers, I think you mean the gravitational force on the object.
 
to get uniform motion you need to make the net force on the body equal 0
 
Draw the free body diagram. To move the block the applied force has to be greater than or equal to the oposing frictional force. If it's greater than the frictional force the block will accelerate. The problem states it's "uniform speed" so it's not accelerating. Leading to the obvious answer.

As for "How much work is done" remember that

Work = force * distance
 
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