Equilibrium on Incline: Solving for Fn with Fg and Θ | 3.80 kg Block | N Units

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A 3.80 kg block is in equilibrium on a 38.4° incline, and the gravitational acceleration is 9.81 m/s². The calculations for the forces involved include Fg sin Θ and Fg cos Θ, resulting in values of 24.04 N and 28.49 N, respectively. The user initially received incorrect feedback from an online assignment, leading to confusion about the calculations. It was suggested that errors might be due to input mistakes in the calculator, and clarification was provided regarding the notation used in the equations. Ultimately, the correct approach to determining the normal force (Fn) was confirmed.
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Homework Statement



A 3.80 kg block is in equilibrium on an incline
of 38.4◦.
The acceleration of gravity is 9.81 m/s2 .
What is Fn of the incline on the block?
Answer in units of N.

Homework Equations





The Attempt at a Solution



FgsinΘ=mgsinΘ=3.8*9.81*sin38.4°=24.04
FgcosΘ=mgcosΘ=3.8*9.81*cos38.4°=28.49

This is from an online assignment. The second equation should've given me the correct value, but when I input the answer, the system tells me it's incorrect. Could anyone enlighten me on this situation? Maybe I'm doing something wrong. Please I would appreciate a quick reply. Thank you.
 
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I get 29.21.
 
Oh hehe I must've made a mistake while calculating. Thank you very much. It's correct.
 
KB94 said:
FgsinΘ=mgsinΘ=3.8*9.81*sin38.4°=24.04
FgcosΘ=mgcosΘ=3.8*9.81*cos38.4°=28.49

I get the same as ideasrule. You have both of your answers off, so there must be something wrong with the way you are typing them into the calculator.

Also, I'm not sure what you mean by FgcosΘ=mgcosΘ. What is Fg? You should probably write it as:

F=mgcosΘ
 
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