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- Thread starter Billyboy777
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Merlin3189

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Yes you're quite right.

When you throw the ball at an angle, you can think of its motion as having two components - one in the direction the train is moving and one perpendicular to it, ie sideways.

And you want the component in the direction of the train to be exactly the opposite of the train's motion.

One way to see how fast this is for any direction, is to draw a scale diagram: draw an arrow backwards equal to the trains speed, then draw a line perpendicular until it meets the line of the ball's direction. Then the length of the line along the ball's direction tells you the speed you have to throw it. (I'll post a diagram as soon as I can do one.)

You can use a calculator and do some physics mumbo jumbo - just divide the speed of the train by the cosine of the angle you throw the ball and that's how fast you must throw it.

When you throw the ball at an angle, you can think of its motion as having two components - one in the direction the train is moving and one perpendicular to it, ie sideways.

And you want the component in the direction of the train to be exactly the opposite of the train's motion.

One way to see how fast this is for any direction, is to draw a scale diagram: draw an arrow backwards equal to the trains speed, then draw a line perpendicular until it meets the line of the ball's direction. Then the length of the line along the ball's direction tells you the speed you have to throw it. (I'll post a diagram as soon as I can do one.)

You can use a calculator and do some physics mumbo jumbo - just divide the speed of the train by the cosine of the angle you throw the ball and that's how fast you must throw it.

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Yes you're quite right.

When you throw the ball at an angle, you can think of its motion as having two components - one in the direction the train is moving and one perpendicular to it, ie sideways.

And you want the component in the direction of the train to be exactly the opposite of the train's motion.

One way to see how fast this is for any direction, is to draw a scale diagram: draw an arrow backwards equal to the trains speed, then draw a line perpendicular until it meets the line of the ball's direction. Then the length of the line along the ball's direction tells you the speed you have to throw it. (I'll post a diagram as soon as I can do one.)

You can use a calculator and do some physics mumbo jumbo - just divide the speed of the train by the cosine of the angle you throw the ball and that's how fast you must throw it.

View attachment 89081

Amazing, thanks.

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