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Physics - effect of speed on drag

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1. In my physics test i had a question which i'm just not too sure about.

There were two of the same balls shape and size, travelling through two different tubes containing one warm oil and one cold oil. The ball in the warm oil traveled faster than in the cold oil. By 40 cm the cold oil had reached terminal velocity, but the other ball was still accelerating

The question asked whether the drag experienced by the ball in the warm oil was equal to, greater than or less than the drag experienced by the ball in the cold oil. I presumed that because it was travelling at a faster speed downwards through the liquid then it will have a greater drag? Or is the drag greater for the cold oil at 40 cm because it's at terminal velocity?

2. (Original post by BDunlop)
In my physics test i had a question which i'm just not too sure about.

There were two of the same balls shape and size, travelling through two different tubes containing one warm oil and one cold oil. The ball in the warm oil traveled faster than in the cold oil. By 40 cm the cold oil had reached terminal velocity, but the other ball was still accelerating

The question asked whether the drag experienced by the ball in the warm oil was equal to, greater than or less than the drag experienced by the ball in the cold oil. I presumed that because it was travelling at a faster speed downwards through the liquid then it will have a greater drag? Or is the drag greater for the cold oil at 40 cm because it's at terminal velocity?

less than because the time it took to reach 40 seconds for the oil was less so it accelerates faster and is travelling at a faster velocity.
3. I suggest you look at your drag/terminal velocity calculations.

The balls are the same, but the oil is not. What properties will change by the oil being warmer and what effect will this have on the drag/terminal velocity inputs/equation?
4. the drag was less in the hot oil because it had a higher rate of acceleration because the oil was less dense

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