How Do You Calculate the Upward Force When a Calculator Rebounds Off the Floor?

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To calculate the upward force exerted on a calculator rebounding off the floor, first determine the force of gravity acting on it, which is 4.9 N. The calculator's rebound involves analyzing its velocity just before and after impact, which can be derived using kinematic equations. The upward force must account for both the gravitational force and the additional force due to the calculator's acceleration during the rebound. The contact time with the floor is also crucial for calculating the net force. Understanding these principles will clarify how to find the upward force effectively.
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Homework Statement


[/B]
Gr.11 Physics, about 2 months in so I don't know much.

Bob pitches his calculator into the air and watches it rise to a height of 5 meters above the floor, and rebound to a height of 4 meters. The calculator was in contact with the floor for ten milliseconds, and it has a mass of 500 grams. Calculate the upward force exerted on the calculator by the floor.

Homework Equations



Here's all the equations I think would be relevant?:

Fn = Fg
Fg = mg
Ff = uFn
Fnet = ma

The Attempt at a Solution



I'm not entirely sure where to start with such little info. I tried to get the Force of Gravity (Fg) like this:

Fg = mg
= (0.5kg)(9.8)
= 4.9N

But I feel like the fact that it was accelerating towards the ground would increase that?

Any help is appreciated.
 
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BrodieEX said:
Here's all the equations I think would be relevant
No, none of those are interesting here.
Does SUVAT mean anything to you?
What about a relationship between force and momentum?
 
haruspex said:
No, none of those are interesting here.
Does SUVAT mean anything to you?
What about a relationship between force and momentum?

No, and no :/ My teacher has a habit of giving us questions for things he hasn't taught us yet. Could you explain?
 
Ah I found a video on exactly what I was looking for. I got it now :)
 
Try to calculate the velocity right before and after the calculator hits the floor and see if you can use this to figure out the force
 
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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