Solving a Ball Thrown off a Cliff: How Long Does it Take?

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A ball is thrown from a cliff at a speed of 6 m/s and an angle of 25°, landing 15 m away from the base. The time for the ball to hit the ground was calculated as approximately 2.76 seconds using horizontal motion equations. Participants noted issues with the clarity of visual aids provided, suggesting better quality images for analysis. The next step involves applying vertical motion equations to determine the height of the cliff based on the calculated time of flight. The discussion emphasizes the importance of clear visuals and proper equations in solving physics problems.
NotInMrPutmansClass
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Homework Statement
Find the height of a cliff using a ball thrown at an angle and find how long it takes the ball to hit the ground.
Relevant Equations
a-sinA, aCosA
This is the question:
A ball is thrown with a speed of 6m/s at an angle of 25° above the horizontal from the top of a cliff. The ball strikes the ground 15 m from the bottom of the cliff.

How long does it take the ball to strike the ground?

How long is the cliff?Here's a visual representation of the problem.
Kinematics 1.jpg

I broke the angle into vectors
Kinematics 2.jpg


I solved for the time of the ball in the
x-axis

t=d/v
t=15m / 5.4378m/s
t = 2.7584 Seconds

But now I'm stuck and I'm lost on what to do next
 
Last edited:
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Welcome to PF.

I'm not able to see much in your attached images -- I seem to only be seeing thumbnail-size images and they are not well lit. Could you maybe use a printer/scanner to generate better copies?
 
NotInMrPutmansClass said:
But now I'm stuck and I'm lost on what to do next
After you post legible figures, you should write the appropriate equation(s) for the motion in the vertical direction.
 
berkeman said:
Welcome to PF.

I'm not able to see much in your attached images -- I seem to only be seeing thumbnail-size images and they are not well lit. Could you maybe use a printer/scanner to generate better copies?
I reposted the pictures and they seem to be fine now.
 
NotInMrPutmansClass said:
I reposted the pictures and they seem to be fine now.
What's the problem with getting the height of the cliff, now you have the time of flight?
 
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