Gravity is counteracted by centripetal force, due to acceleration, which is the force that pushes you into your seat.
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Answer:
A. 
B. 
C. 
D.
Explanation:
Given:
- no. of moles of oxygen in the cylinder,

- initial pressure in the cylinder,

- initial temperature of the gas in the cylinder,

<em>According to the question the final volume becomes twice of the initial volume.</em>
<u>Using ideal gas law:</u>



A.
<u>Work done by the gas during the initial isobaric expansion:</u>




C.
<u>we have the specific heat capacity of oxygen at constant pressure as:</u>

Now we apply Charles Law:



<u>Now change in internal energy:</u>



B.
<u>Now heat added to the system:</u>



D.
Since during final cooling the process is isochoric (i.e. the volume does not changes). So,
For this case we have that according to Newton's second law it is true that:

Where:
F: It is the force
m: It is the mass
a: It is the acceleration
According to the data we have:

So, we have:

Thus, the applied force will be 7 Newtons.
Answer:

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