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You are riding on a bike. In which of the following situations are the forces acting on the bike balanced?

A) you pedal to speed up B) you turn at a constant speed. C) you coast to slow down D) you pedal at a constant speed. which one? please help thanks!

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If the forces on a body are not in balance, the body will accelerate or decelerate.

Remember, moving in a circle requires constant acceleration, even though your speed isn't changing.

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I was riding to work one morning and was pulled up at traffic lights in very heavy traffic. As I stopped I flicked off the toe clip so I could put my foot on the ground, then over-balanced the other way, still locked in.

SPLAT!

And you'd never believe it was right in front of Sydney University. What a place I chose to look stupid.
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Been there, done that Duffy. Ever tried 'clipless' pedals? They're murder until you get used to 'em. You KNOW you're going to fall over on every ride of the first 2 or 3....
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They weren't around when I was training, John. They look very good.
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Thanks wittepier!
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D. If you stop pedaling the bike will tip over to one side .

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Thanks!
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Have you ever actually ridden a bike? When you coast, you keep going for a while. People usually coast when their legs are tired and need a break, and so far I haven't fallen over from that.
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Thank you for your opinion I will take not of it .(:
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* note
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Okay well you slow down when you turn, so that's not it. Coasting mainly causes to move at a constant speed for a while, plus if you're going downhill and coasting you'll just speed up (and usually you hit the breaks to slow down). It's up to you to figure out if it's A or B. Not too hard, don't worry.

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when you stop pedaling and coast there is an unbalanced force on the bike, That is friction with the road, slowing the bike down. To balance this force you need to pedal, so coasting is an unbalanced situation, not balanced as the question asks. The correct answer is that the forces are balanced when no change in speed occurs, which is when you are pedaling at a constant speed, D
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There is always an unbalanced force on the bicycle. That's why it moves. I understand friction, but when I want to slow down, I hit the breaks. It's much quicker that way, you know.
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No, when a bike is standing still, or when it is moving at a constant speed the forces are balanced. Unbalanced forces result in a change in velocity, either in speed or direction.
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I think you mean acceleration, not velocity. Just sayin'.
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The definition of acceleration is a change in velocity. Velocity is a vector measurement (speed and direction).
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You think I don't know that? Dude, I take Physical Science. This is all fresh in my mind.
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So, you know that unbalanced forces always result in a change in velocity (delta V), but only sometimes result in a change in acceleration. Acceleration can remain constant under unbalanced forces.
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But unbalanced forces most always change acceleration, whether it's positive or negative. When you slow down, there is an unbalanced force, and you have a negative acceleration. When you speed up there is an unbalanced force and you have a positive acceleration. When you're turning a corner, there is an unbalanced force and you are accelerating. I understand that velocity is a major factor, but practically any time there is an unbalanced force there is a change in acceleration.
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Absolutely not. An unbalanced force results in acceleration, which is a change in velocity. A change in acceleration means that the rate of acceleration changes, which must mean that the forces are changing, too. Now, think of slowing down and stopping. The rate of acceleration changed from some value to zero. But now that you're stopped the forces are balanced. So a change in velocity (acceleration) is NOT the same as a change in acceleration, they are two different concepts.
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Dude it's been 12 days, just drop it.
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Just trying to help you understand a concept that you obviously don't grasp. Sorry you find that annoying.
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I understand the concept completely. You're just pissing me off now.
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