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Hello
Here's the question exactly copied:

You're in a bus moving on a level road. You throw a ball vertically upward and wait for it to descend vertically into your hand. Will it descend into your hand, too far forward, or too far backward? Give answers in the case the bus is moving at constant velocity, and in the case the bus is accelerating forward.

I'm guessing the ball will fall back into my hand at constant velocity, and it will go backwards in forward accel.

Does anyone know the answer? And can explain
Barbarella -love-
Hello
Here's the question exactly copied:

You're in a bus moving on a level road. You throw a ball vertically upward and wait for it to descend vertically into your hand. Will it descend into your hand, too far forward, or too far backward? Give answers in the case the bus is moving at constant velocity, and in the case the bus is accelerating forward.

I'm guessing the ball will fall back into my hand at constant velocity, and it will go backwards in forward accel.

Does anyone know the answer? And can explain
You are correct on both counts.

The reason the ball will fall back into your hands if the bus is moving at a constant speed in the same direction is because when the ball goes into the air, it doesn't just move upwards, it also moves forward like it was before. It looks really differently if you're watching from the road or the bus. From the road, it looks like the ball is always moving forward at the same speed as the bus and whoever throws it. When you toss it up you add some upward motion to it's forward motion, so it moves in an arch. The upward motion doesnt change the forward motion.

When you're accelerating, speeding up, the ball will not land like it did before because while the ball is in the air, you're gaining speed. You move faster than the ball does so the ball lands behind where it was thrown.
Vannak
Barbarella -love-
Hello
Here's the question exactly copied:

You're in a bus moving on a level road. You throw a ball vertically upward and wait for it to descend vertically into your hand. Will it descend into your hand, too far forward, or too far backward? Give answers in the case the bus is moving at constant velocity, and in the case the bus is accelerating forward.

I'm guessing the ball will fall back into my hand at constant velocity, and it will go backwards in forward accel.

Does anyone know the answer? And can explain
You are correct on both counts.

The reason the ball will fall back into your hands if the bus is moving at a constant speed in the same direction is because when the ball goes into the air, it doesn't just move upwards, it also moves forward like it was before. It looks really differently if you're watching from the road or the bus. From the road, it looks like the ball is always moving forward at the same speed as the bus and whoever throws it. When you toss it up you add some upward motion to it's forward motion, so it moves in an arch. The upward motion doesnt change the forward motion.

When you're accelerating, speeding up, the ball will not land like it did before because while the ball is in the air, you're gaining speed. You move faster than the ball does so the ball lands behind where it was thrown.

Okai thank you ^_^
I figured that's how it was but I wasn't too sure why though.
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

Kindly Seeker

Cogent Dream
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

I think for the relatively short distances involved with buses and balls, air resistance is negligible. Unless you have some sort of super-precise laser measuring equipment that can detect a change in position of the ball by a couple femtometres. whee
Amy Reinvented
Cogent Dream
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

I think for the relatively short distances involved with buses and balls, air resistance is negligible. Unless you have some sort of super-precise laser measuring equipment that can detect a change in position of the ball by a couple femtometres. whee

Depends how high you throw it. But if you did it in real life it most likely would fall behind you.
Cogent Dream
Amy Reinvented
Cogent Dream
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

I think for the relatively short distances involved with buses and balls, air resistance is negligible. Unless you have some sort of super-precise laser measuring equipment that can detect a change in position of the ball by a couple femtometres. whee

Depends how high you throw it. But if you did it in real life it most likely would fall behind you.
In the context of the problem, it probably wouldn't. Friction only acts in the direction of motion so if you're throwing the ball straight up while moving at a constant velocity, unless there's some breeze (which doesn't have to happen in a sealed bus), then the ball should act exactly as if you were to throw it straight up in a closed room.
Vannak
Cogent Dream
Amy Reinvented
Cogent Dream
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

I think for the relatively short distances involved with buses and balls, air resistance is negligible. Unless you have some sort of super-precise laser measuring equipment that can detect a change in position of the ball by a couple femtometres. whee

Depends how high you throw it. But if you did it in real life it most likely would fall behind you.
In the context of the problem, it probably wouldn't. Friction only acts in the direction of motion so if you're throwing the ball straight up while moving at a constant velocity, unless there's some breeze (which doesn't have to happen in a sealed bus), then the ball should act exactly as if you were to throw it straight up in a closed room.

But if you're travelling at a constant velocity, the ball leaves your hand at the same velocity in a horizontal vector. Meanwhile, air is stationary, thus friction. Basically the same as riding a bike really fast and feeling it on your face (because the ball is also travelling both upwards and in whatever direction you're driving).
Cogent Dream
Vannak
Cogent Dream
Amy Reinvented
Cogent Dream
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

I think for the relatively short distances involved with buses and balls, air resistance is negligible. Unless you have some sort of super-precise laser measuring equipment that can detect a change in position of the ball by a couple femtometres. whee

Depends how high you throw it. But if you did it in real life it most likely would fall behind you.
In the context of the problem, it probably wouldn't. Friction only acts in the direction of motion so if you're throwing the ball straight up while moving at a constant velocity, unless there's some breeze (which doesn't have to happen in a sealed bus), then the ball should act exactly as if you were to throw it straight up in a closed room.

But if you're travelling at a constant velocity, the ball leaves your hand at the same velocity in a horizontal vector. Meanwhile, air is stationary, thus friction. Basically the same as riding a bike really fast and feeling it on your face (because the ball is also travelling both upwards and in whatever direction you're driving).
In the context of being on a bus, it's not a wild assumption to say that the windows may be down and the air would be moving with you.
Vannak
Cogent Dream
Vannak
Cogent Dream
Amy Reinvented
Cogent Dream
Theoretically, you're right. But it would only work in a vacuum.

Practically speaking you'd have to factor in air resistance at the very least.

I think for the relatively short distances involved with buses and balls, air resistance is negligible. Unless you have some sort of super-precise laser measuring equipment that can detect a change in position of the ball by a couple femtometres. whee

Depends how high you throw it. But if you did it in real life it most likely would fall behind you.
In the context of the problem, it probably wouldn't. Friction only acts in the direction of motion so if you're throwing the ball straight up while moving at a constant velocity, unless there's some breeze (which doesn't have to happen in a sealed bus), then the ball should act exactly as if you were to throw it straight up in a closed room.

But if you're travelling at a constant velocity, the ball leaves your hand at the same velocity in a horizontal vector. Meanwhile, air is stationary, thus friction. Basically the same as riding a bike really fast and feeling it on your face (because the ball is also travelling both upwards and in whatever direction you're driving).
In the context of being on a bus, it's not a wild assumption to say that the windows may be down and the air would be moving with you.

Sorry, I was actually imagining it being a person on top of a moving vehicle throwing it up into the air. When I heard throwing I just assumed a decent distance (one body length or something).

Dapper Reveler

Depends on how steady you throw it.

Quotable Genius

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Barbarella -love-
Hello
Here's the question exactly copied:

You're in a bus moving on a level road. You throw a ball vertically upward and wait for it to descend vertically into your hand. Will it descend into your hand, too far forward, or too far backward? Give answers in the case the bus is moving at constant velocity, and in the case the bus is accelerating forward.

I'm guessing the ball will fall back into my hand at constant velocity, and it will go backwards in forward accel.

Does anyone know the answer? And can explain

It doesn't fall back at constant velocity. It accelerates.

If the bus is accelerating forwards, the ball will drop behind you.