Relative motion with cart and ball

AI Thread Summary
A cart moves horizontally at 10 m/s while a ball is ejected vertically from it. The ball reaches its maximum height 2 seconds after launch, prompting questions about the angle of ejection and the ball's initial velocity. The first question asks if the angle θ, as seen from the cart, is greater than 90 degrees, with the consensus leaning towards false. For the second question, there is confusion regarding the initial velocity of the ball relative to the cart, with options ranging from 10 m/s to 30 m/s, and uncertainty about the application of the relative motion formula. Understanding relative motion is crucial for solving these problems accurately.
ryan1180
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Homework Statement



A cart moves with velocity vC = 10 m/s in the horizontal direction as shown below.

[PLAIN]https://online-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys100/fall10/hwb/04/01/cart.gif

A ball is ejected from the cart with an initial velocity vB with respect to the cart such that an observer on the ground sees the ball move directly vertical. The ball reaches its maximum height at a time t = 2 s after it is launched. The next two questions pertain to this situation.

1) The angle θ (as measured by someone on the cart) is greater than 90 degrees.

(True or False)

2) What is vB, the magnitude of the initial velocity of the ball with respect to the cart?

vB = 10 m/s
vB = 18 m/s
vB = 22 m/s
vB = 26 m/s
vB = 30 m/s
(multiple choice)


Homework Equations



vB=vBC+vCG

The Attempt at a Solution



I'm pretty sure that the answer to part 1 is false

For part 2 I think the answer is 10, but I get confused with relative motion...
 
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Am I at least using the correct formula for this? I'm not even sure about that...
 

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