I don't think it was very clear- it just said how would it compare?
What did you write for it?
Well Terminal velocity during free fall occurs when the weight of the object is being balanced by air resistance. The weight in both is the same. Therefore the speed it travels depends on the time taken for it to reach terminal velocity. The more the time taken the more time the unbalanced force acts upon it and therefore it keeps on accelerating for longer and therefore the more the speed. Air resistance depends on the speed (which is what is being questioned), the density of the medium (which remains the same) and the surface area exposed to collisions with the air particles. When 3 parachutes are working the more the surface area, therefore the more the air resistance, and the less the time it takes for air resistance to balance its weight. Therefore it accelerates for less time and therefore as V=at the speed during terminal velocity is less. I just wrote "2 parachutes mean less SA, therefore less air resistance, therefore for air resistance to balance weight speed must be greater, as air resistance increases with speed"
Well Terminal velocity during free fall occurs when the weight of the object is being balanced by air resistance. The weight in both is the same. Therefore the speed it travels depends on the time taken for it to reach terminal velocity. The more the time taken the more time the unbalanced force acts upon it and therefore it keeps on accelerating for longer and therefore the more the speed. Air resistance depends on the speed (which is what is being questioned), the density of the medium (which remains the same) and the surface area exposed to collisions with the air particles. When 3 parachutes are working the more the surface area, therefore the more the air resistance, and the less the time it takes for air resistance to balance its weight. Therefore it accelerates for less time and therefore as V=at the speed during terminal velocity is less. I just wrote "2 parachutes mean less SA, therefore less air resistance, therefore for air resistance to balance weight speed must be greater, as air resistance increases with speed"
That makes perfect sense! I wrote that because drag force has decrease, it takes longer to reach terminal velocity (but then I think I negated any marks I may have got by saying that the terminal velocity is the same in both cases silly silly silly me)
Btw, you know the coin question did the area of the coin stay the same and you had to x the weight by 8 so the equation for pressure of the coin was 0.288 divided by 0.0013 ?
I guess it depends on your take on the question Because they had asked you for the equation in the question above, and because the question was 3 marks on its own, I thought that was too simple
78W in one day right? So if you just multiply it by 10, then that would be the power in 10 days...
Btw, you know the coin question did the area of the coin stay the same and yo had to x the weight by 8 so the equation for pressure of the coin was 0.288 divided by 0.0013 ?
What did everyone write for the terminal velocity question and the stupid smoke detector/radon question?
for the alpha particle gas Q about why it was had new health risks in the gas was because one the smoke alarm was a solid so alpha particles didn't have as much kinetic energy as the particles in the Radon gas? and can therefore travel in the human air that is breathed in? I have no idea of that's right or not but I just made a logical guess.. hope I got the marks haha
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