Does force normal change when you push an object at an angle?

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When pushing an object at an angle, the normal force is affected by both the gravitational force and the vertical component of the applied force. The force of gravity acting on the lawn mower remains constant at 123.48 N, calculated using its mass and gravitational acceleration. The vertical component of the applied force, which is 65.5 N downward, increases the normal force to 188.98 N. This occurs because the applied force adds to the weight of the mower, pressing it more firmly against the ground. The gravitational force itself does not change with the application of an external force, as it is dependent solely on the mass of the object.
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Homework Statement



You exert a force of 131 N [30° below horizontal] onto a 12.6 kg lawn mower, What is the force of gravity and normal force on the lawn mower?

Homework Equations


Fg= m × g
FA (y component) = Sin30° × FA

The Attempt at a Solution


The force of gravity is equal to the force of normal,
∴ FN = m × g
= 12.6 kg × 9.8 m/s2
= 123.48 [up]​

But, the normal force gets added on by the force opposing the y component of the applied force right?

So, FA (y component)Sin30° × FA
= 65.5 N [down]​
So by Newtons 3rd law there would be a force acting up on the lawn mower of 65.5 N[up].I'm just wondering if these two forces are added to each other for the total normal force which is 123.48 N + 65.5 N = 188.98 N [up]?
 
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Yes, all correct. The vertical component of the push adds to the weight to make the normal force pressing the mower down on the ground.
 
Thanks, but I have a question. Why doesn't the force of gravity on the lawn mower increase when you apply your force on it? Aren't you essentially making the lawn mower heavier?
 
The force of gravity depends on the MASS of the mower. You probably know it is
Fg = GMm/d² where M is the mass of the Earth and m the mass of the mower.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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