Magnitude and Direction of Normal FOrce

AI Thread Summary
To determine the normal force acting on the second tier of a three-tiered birthday cake weighing 9 N, one must consider the weight of the tiers above it. The total weight supported by the second tier includes the weight of the top tier (5 N) plus its own weight (9 N), resulting in a total of 14 N. Since the cake is stationary, the normal force must equal this total weight, thus the normal force is 14 N acting upwards. Understanding Free Body Diagrams is crucial for visualizing the forces at play, as they help clarify the balance of forces in static systems. Properly applying Newton's laws will lead to accurate calculations of forces in mechanics.
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Homework Statement


A three-tiered birthday cake rests on a table. From bottom to top, the cake tiers weigh 16 N, 9 N, and 5 N, respectively. What is the magnitude and direction of the normal force ating on the second-tier?


Homework Equations


FN=FWcos(theta)


The Attempt at a Solution


5 N = .51 kg
9 N = .92 kg
16 N =1.6 kg
 
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becsantos said:

Homework Statement


A three-tiered birthday cake rests on a table. From bottom to top, the cake tiers weigh 16 N, 9 N, and 5 N, respectively. What is the magnitude and direction of the normal force ating on the second-tier?


Homework Equations


FN=FWcos(theta)
Where did you get this equation? Resist the temptation to memorize equations from other example problems, that will only serve to confuse you. Keep it basic. Everything is in the vertical direction, and nothing is moving, so sum forces in the vertical direction = 0 , when looking at Free Body Diagrams. Please get familiar with them, as they are essential in the study of mechanics. In a Free Body Diagram, you isolate the system , or part of the system, and examine the forces acting on it, both contact forces (like normal forces) and non-contact forces (like gravity), and apply Newton's laws. Give it a try.

The Attempt at a Solution


5 N = .51 kg
9 N = .92 kg
16 N =1.6 kg[/QUOTE]
 
I don't know how to find an answer please help
 
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