A weird math question?

Question

If a flatbed truck is traveling at 20 mph in one direction and you ride a bicycle off the flatbed in the other direction at 20 mph what the heck would happen?

Answer 1

I assume you mean the bicycle is going 20mph relative to the truck. That means it's not moving relative to the ground. If you're a good stunt rider, dropping the three feet to the ground won't bother you. You won't be moving relative to the ground. Again, if you're a good stunt rider, that won't bother you either. The crowd watching you will applaud. You'll say to yourself, "Dude, that was way cool!" You'll put the video online and become a little famous.

If you're not a good stunt rider, your body will hurt and your pride will hurt worse.

Answer 2

There is some problem in your question. The truck velocity is 20 mph wrt the ground, but is the bike going 20 mph wrt the ground or wrt the truck bed?

Velocity is a vector, so if the truck and the bike are going 20 mph with wrt the ground in opposite directions, the bike will hit the ground at 20 mph. But to go 20 mph wrt the ground, the bike needs to be going 40 mph wrt the flatbed and in the direction opposite to the flatbed's direction.

This follows because v = Vt - Vb = 20 - 40 = -20 mph; where v is the velocity of the bike wrt the ground, Vt is the truck velocity, and Vb is the bike velocity wrt the truck. The negative sign means the bike hits the ground in a direction opposite to that of the truck.

Answer 3

Since the speed is constant, unfirom, then acceleration is 0 for both objects and since the bicycle is relative to the trucks platform the only thing observed would be. The truck wheels normaly move and travel a distance, but it would seem as if the bicycle is not moving at all when it actually is. But since the truck makes but the distance that the bike rides witin a certain instand due to having same speed, the bike would remain in the same position and only the wheels would seem to be moving and not the bike. If this is continued for days then sooner or later the wheels would probably break or the bike would sooner or ralter generate enought head to slowly make the trucks platform wear away, and then the bike would fall off. But probably the bikes wheels would fall off first and the person atop the bike would fall, since the person has no speed to create(especially 20mph) he would fall off the truck and dependent if the road is extremely sharp the person would get injured preety bad.

Answer 4

You are sittng still on the truck. if you jumped straight up the truck would drive out from under you. how ever were you to jump form the truck you would leave at 20 miles an hour. That coupled with you dong 20 an hour on your own would send you out at 40.
Any one who thinks they would not be going 20 miles an hour when they hit the ground(on foot) jump off first with the truck standing still , than jump with it moving at 5 miles an hour, 10, miles , 15 miles an houtr and than 20. That is why people who jump out of slow moving box cars always roll when they hit the ground. even if they out run it and climb in they would leave the same speed as the train if they jumped. So i fyou left the truck at 20 on your bike I think you wouldhit the ground at 40. and bust some butt.

Answer 5

i believe it depends on what you do once you jump off the end of the trailer

if you engage the brakes and stop the wheels in midair, you could achieve a stable, stationary landing. if you keep pedaling at the same rate, you'll hit the road standing still, then very quickly accelerate up to 20 mph. if you just let the wheels spin freely, you'll accelerate, but not as much because some amount of momentum will be lost to friction. how much depends on the state of your tires, type of roadway, axle lubrication, etc.

Answer 6

Do you think you can get the bike up to 20 mph before you run out of truck? If you can, you will be stationary relative to the ground at the time. I won't want to be you when you landed.

Answer 7

it depends- are you moving at 20mph in relation to the ground or to the truck?

if it is to the ground, you will be moving at 20mph in the opposite direction, assuming you could handle the landing and all

if it is in relation to the truck, you would land sitting pretty still, once again negating the effects of bouncing and all

Answer 8

Not math answer -- you would wipe out, hard
Math answer -- reletive to the ground you would be moving 0mph and have no momentum in any direction

Answer 9

Youd land not moving at all in relation to the ground

Answer 10

You would be going twenty miles a hour backwards and stand a good chance of getting hurt. The faster you go the worse it would be.