Suppose that you want to move a heavy box with mass 30.0 kg across a carpeted floor. You try pushing hard on one of the edges, but the box does not move. Suppose that you are pushing against the box from an angle 30.0 above horizontal with a force of magnitude 240 N. What is the magnitude of the friction force acting on the box?
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I have some help here:
http://lettergram.net/newtons-three-laws…
The key idea though is that there is 30kg * 9.8 m/s^2 which equals 294N downwards from the box.
You then push the box with an angle of 30 degrees from the horizontal with a force of 240N.
So we take 240N * sin(30)
*(to get the downward force you are applying!)
240N * sin(30) = 120N downwards
so add the 120N + 240N = 360N downward force.
Now by definition the force due to friction is μ * Fn (force normal)
μ is the coefficient due to gravity, which was not stated in the problem.
Force normal is the force pushing back on the box and since we know the box is being pushed down with 360N we know Fn is equal to 360N!
so the ANSWER is the Ff (force due to friction) = μ * (360N)
If you have any further questions I will again be looking at this problem so feel free to add additional details or simply visit me at lettergram.net (for a likely quicker response!).
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Well because it asks for the magnitude of the friction force acting on the box,
"Ff (force due to friction) = μ * (360N)" Should be correct, or 360 time larger than μ.
Also if you still have any questions on forces:
http://lettergram.net/forces/
I made a lovely pdf or word document to download or view.
Anyways hope that satisfies your teacher, if it does feel free to choose me as your answer :)
If not I don't blame you...
http://lettergram.net/newtons-three-laws…
The key idea though is that there is 30kg * 9.8 m/s^2 which equals 294N downwards from the box.
You then push the box with an angle of 30 degrees from the horizontal with a force of 240N.
So we take 240N * sin(30)
*(to get the downward force you are applying!)
240N * sin(30) = 120N downwards
so add the 120N + 240N = 360N downward force.
Now by definition the force due to friction is μ * Fn (force normal)
μ is the coefficient due to gravity, which was not stated in the problem.
Force normal is the force pushing back on the box and since we know the box is being pushed down with 360N we know Fn is equal to 360N!
so the ANSWER is the Ff (force due to friction) = μ * (360N)
If you have any further questions I will again be looking at this problem so feel free to add additional details or simply visit me at lettergram.net (for a likely quicker response!).
---------------------------------------…
Well because it asks for the magnitude of the friction force acting on the box,
"Ff (force due to friction) = μ * (360N)" Should be correct, or 360 time larger than μ.
Also if you still have any questions on forces:
http://lettergram.net/forces/
I made a lovely pdf or word document to download or view.
Anyways hope that satisfies your teacher, if it does feel free to choose me as your answer :)
If not I don't blame you...
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Answer is 208N
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