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# few questions about newton's 2nd law that i'm stuck on =[ watch

1. An 80kg skier has a force 200N exerted on him down a slope.
Calculate his aceleration down the slope.
Is the slope less than or more than 45(degrees)? explain your answer.

80 x 9.81 = 784.8N

I'm not sure which one of these is right...

200N = 80 x a
a = 2.5 m/s^2

or

x

I'm not sure how to work out the second part.

Thanks!!
any help will be greatly appreciated!
and +rep to the person who offers the most thorough and conclusive answer!
2. 200N = 80 x a
a = 2.5 m/s^2

thats right

well it says 'explain' so no calculation generally needed...so my guess would be more but i dont have a proper answer to that....just cant imagine someone whose 80kgs going down a slope at 2.5ms-1 at an angle less than 45
sorry thts all i can do atm
3. (Original post by Spongebob*No*Pants)
An 80kg skier has a force 200N exerted on him down a slope.
Calculate his aceleration down the slope.
Is the slope less than or more than 45(degrees)? explain your answer.

80 x 9.81 = 784.8N

I'm not sure which one of these is right...

200N = 80 x a
a = 2.5 m/s^2

or

x

I'm not sure how to work out the second part.

Thanks!!
any help will be greatly appreciated!
and +rep to the person who offers the most thorough and conclusive answer!

Well you've worked out the acceleration, a = 2.5 m/s^2.

And if you think about a block sliding down a slope, the acceleration of the block is if the angle of the slope is theta.

so the angle of this slope is:

which is less than 0.7 (which sin 45 approximately equals), so the slope is less than 45 degrees.

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