(adsbygoogle = window.adsbygoogle || []).push({}); First Question:

A 0.45 N block is given on initial velocity of 5.3 m/s along a horizontal surface. If the coefficient of friction between the block and the surface is 0.25, how far will the block move before coming to rest? How long will it take the block to stop?

Second Question:

A hospital attendant exerts a horizontal force of 60.0 N on a gurney with a patient on it and accelerates at 0.400m/s[tex]^{2}[/tex]. The patient is 65.0 kg and the gurney is 30.0 kg. What is the magnitude of the frictional force opposing the motion?

Third Question:

A military plane wants to drop supplies to some survivors on a rocky ridge. The plane flying horizontally at an altitude of 235 m with a speed of 72.5 m/s. How far in advance must the relief goods be released so that they arrive precisely at the survivors' location?

Fourth Question:

The coefficient of sliding friction between a metal block and the inclined plane surface over which it will slide is 0.200. If the surface makes an angle of 20.0 degrees with the horizontal and the block has a mass of 80.0 kg, what force is required to slide the block at constant speed up the plane?

I know the formulas but I do not know how to use them properly. I mean I know how to derive from this to this but in this cases, these are problems I'm not familiar with so I don't know how to do. In usual cases, after my coach or teacher has solved them, I would just realized that I know how to do it and I know that type of solution but I just don't know that it's the one we're looking for or it's just that kind of solution I need.

I hope you could help me. :) Thanks!

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