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nelan · Oct 3, 2009, 07:38 PM

A basketball player throws the ball at a 50degree angle above the horizontal to a hoop which is located a horizontal distance L = 8.0m from the point of release and at a height h = 3.1m above it.

nelan · Oct 3, 2009, 07:38 PM

A baseball bat makes contact with a ball 0.8 meters above the ground and the ball moves away at a 36.5 degree angle from the horizontal. It's a homer! The ball lands in the bleachers (the seats) 138.5 meters away from home plate, 5.7 meters above the ground. How long was the ball in the air? How fast was the ball going when it left the bat?

nelan · Oct 3, 2009, 07:39 PM

A helicopter is flying in a straight line over a level field at a constant speed of 20.2 and at a constant altitude of 22.5 . A package is ejected horizontally from the helicopter with an initial speed of 24.7 relative to the helicopter, and a direction opposite to the helicopter's motion.
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What angle between 0 degrees and 90 degrees does the velocity vector of the package make with the ground at the instant before impact, as seen from the ground?

nelan · Oct 3, 2009, 07:40 PM

A ski jumper acquires a speed of 101.4 km/hr by racing down a steep hill. He then lifts off into the air from a horizontal ramp. Beyond this ramp, the ground slopes downward at an angle of theta= 45 degrees.

nelan · Oct 3, 2009, 07:41 PM

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Clough · Oct 3, 2009, 08:21 PM

Originally Posted by nelan

A basketball player throws the ball at a 50degree angle above the horizontal to a hoop which is located a horizontal distance L = 8.0m from the point of release and at a height h = 3.1m above it.

Hi, nelan!

That's nice. So, what's your question, please?

Have you seen and read the announcement concerning how to ask homework questions on this site that can be found via clicking on the following link?

Ask Me Help Desk - Announcements in Forum : Homework Help

If you haven't read it, please do.

Thanks!

nelan · Oct 3, 2009, 08:28 PM

What is the required speed if the basketball is to reach the hoop?

Curlyben · Oct 4, 2009, 08:59 AM

>Multiple Threads Merged<

Unknown008 · Oct 4, 2009, 09:12 AM

Thanks Ben! :)

Ok nelan, you need to know your formulae and when to use them.

$v = u+at$
$s=ut+\frac12 at^2$
$v^2 = u^2+2as$

s = displacement
u = initial velocity
v = final velocity
t = time
a = acceleration.

1. All the velocities are vectors, so, you have to assign a sign to each of them. For example, if you take the vertical direction as positive in a number, take all the vertical directions as positive values, and the downwards direction as negative direction.

2. Use the formulae I gave you to solve for an unknown. If you have the final velocity, the initial velocity and the acceleration, you can find the time using the first formula, and the displacement in the third formula.

You have to make an attempt to each question, and if you have a problem, you say what you did, and what you don't understand. It's only then that help will be given.