A heavy box is pulled across a wooden floor with a rope. The rope makes an angle of 60° with the floor. A force of 80 N is exerted on the rope. What is the component of the force parallel to the floor?
Did you draw a picture yet?
with a picture and some trig, this becomes really clear.
In this case you need to use the cosine law to calculate the force acting horizontally.
no law involved. You'll have a right triangle
For a problem like this it helps to separate the force acting to the horizontal or vertical. For a known angle to the horizontal use sine law to calculate the force acting up and cosine for the force acting to the horizontal
And yes trig law is invovled. This is not a right triangle.
You have a right triangle...|dw:1444021627335:dw|
@Robert136
well @cheska_P You have a picture now, so it should be pretty easy to get what I meant based off of my argument above
lemme know if you have any questions :)
@FibonacciChick666 I did 80Ncos(60) and got 40N. So would that be answer for the force parallel to the floor?
I didn't check the actual number, but assuming calculator was correct, It would indeed. Now for a mental reasoning. The bottom part of the triangle is parallel to the floor so, we need the trig function that gives us the adjacent. which is cosine so then we know our hype and an angle, so we get cos60=x/80-->80cos60
Nice work :) In these instances, always draw a picture. It helps immensely.
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