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if im riding@80kph in my bike is my speed 80kph or less due to wind resistance

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Type: Question • Score: 6 • Views: 754 • Replies: 14

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@blue train,

In general, air resistance decreases speed relative to the ground, but for the question to make sense, you need to state to what the 80kph is relative. You also need to state the magnitude and direction of the wind speed and to what those measurements are relative.

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Wikipedia wrote:

kph – a physical unit of speed or velocity (non-standard; km/h is usually preferred where SI conformance is important)

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@blue train,

I you're doing 80, you're doing 80. Without the wind resistance (i.e. without the surrounding air), you'd die from asphyxiation and how fast you wre going would be the least of your problems...

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@blue train,

A more realistic/meaningful question: If you're riding a bicycle along the top of a train at 20 kph and the train is moving at 80 kph (wrt the ground), how fast are you moving wrt the ground?? Answer is 100 kph...

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@blue train,

blue train wrote:

if im riding@80kph in my bike is my speed 80kph or less due to wind resistance

Not enough information.

1. Has the rider been eating beans in the preceding 24 hours?
2. Is the bike motorised? Or can you move your legs really really quickly?

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@blue train,

If you are riding at 80 km.p.h. on your bike, you are either one of the biggest liars who ever lived, or you have thighs the size of of a jumbo jet.

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@blue train,

If you are riding 80kph on your motorcycle, you are moving at 80kph. The air resistance only comes into effect if you need to determine the force required to move that speed.

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@Setanta,

Don't really grasp physics, do ya?? Past some point in thigh size, the whole process will stop and Mike Obunga or Hillary or whoever will just sit there on her bicycle wishing for smaller thighs...

1 Reply

@gungasnake,

Don't really grasp humor, do ya?

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@Setanta,

He can't grasp humour, but boy does he make me snort my coffee sometimes.

Hilarious.

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Unintentional humor is always the best.

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@blue train,

Speed is a scalar quantity, Velocity is a vector.

I can be speeding along at 80 km/hr--but my velocity will be 80 km/hr is 80 km/hr only if I traveling 80km/hr East on level ground.

Wind resistance is a Vector force that acts on a speeding body--but it's effect will depend upon the addiction of the vector

Rap

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@raprap,

Quote:

addiction of the vector

1 Reply

@fresco,

Post: # 5,431,552

Rap

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