What is the initial velocity of the stone?

AI Thread Summary
The discussion revolves around a physics problem involving a boy using a slingshot to hit a can at a distance of 15 meters and an elevation of 30 degrees. The calculated x- and y- components of the can's displacement are 12.99 meters and 7.50 meters, respectively. The initial velocity components of the stone are 19.05 meters in the x-direction and 11.0 meters in the y-direction. The stone passes directly below the can after 0.682 seconds, with a height differential of 2.28 meters between the can and the stone's path. The range of the stone is calculated to be 14.0 meters, and it is advised to double-check calculations for accuracy.
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Can anyone tell me if my answers are right or wrong? thanks

A boy with a slingshot wants to hit a can on top of a pole. The can is a distance of 15 meters from the boy at an elevation of 30 degrees above the horizontal. The boy aims the slingshot directly at the can and projects a stone with a speed of 22 meter/second. It misses the can. (We want to find out bad the aim was.)

a) Find the x- and y- components of the displacement of the can from the child.

12.99 x + 7.50 y

b) What is the initial velocity of the stone?

19.05 x + 11.0 y

c) When does the stone pass directly below the can?

0.682 seconds

d) Find the height differential between the can and the path of the stone.

2.28 meters

e) Find the range of the stone (i.e. where it lands).

14.0 meters
 
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Look over (d) and (e) more carefully. The rest of your answers look good. For (d) you will need to use:

y = v_{0y}t - \frac{1}{2}gt^2

For part (e) you can use the same equation and solve for t when y = 0. That will give you the total time of flight. You can then find the range via

x = v_{0x}t
 


Without knowing the specific values used in the calculations, it is difficult to determine if the answers are right or wrong. However, the method and formulas used seem to be correct. It is always a good idea to double check your calculations and make sure they are consistent with the given information and formulas. Additionally, it may be helpful to have someone else check your work to ensure accuracy.
 
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