Finding Net Force on a 725 Gram Block with Given Acceleration and Angle

[ScienceGirl90]

Homework Statement

Find the magnitude of net force on the following object a 725 gram block that is accelerating at 8.10 m/s2 at an angle of 18.0 degree relative to horizontal.

Homework Equations

F=m*a

The Attempt at a Solution

I first converted the 725 grams to kilograms but then after that I am unsure of what to do. Having information about the angle is throwing me off because I don't know what equation to use.

 

[PhanthomJay]

Read up again on Newton's 2nd law, the part about where it talks about the direction of the net force.

 

[ScienceGirl90]

Well I did read that if you know the direction of acceleration, you know the direction of the net force. But I am still confused as to how this helps. Would you please explain more? Thank you!

 

[MillerGenuine]

What you have to do is find your force for your x-component and your force for your y-component and then find the magnitude of these. because its asking for magnitude.
so..
F_x = ma_x
and
F_y = ma_y

so for these equations obviously your mass will be the same value, but you must find your x and y component of acceleration, which is an easy trig problem (draw a triangle)

you should be able to then easily solve for you F_x and F_y
once you find these you should know how to find the magnitude, its the square root of (F_x)^2 + (F_y)^2

 

[PhanthomJay]

But F_net =ma, where m and a are given. It's very easy, don't let the angle trick you.