Finding acceleration and distance

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The discussion revolves around calculating the acceleration and distance of a soccer ball rolling down an incline. The ball, starting from rest, travels 51 meters in 6.3 seconds, with a final time of 7.3 seconds to reach the bottom. The calculated acceleration is 2.57 m/s², and the total distance of the incline is determined to be 68.5 meters. The original poster expresses confusion about their solutions, seeking clarification and confirmation from others. The thread highlights the challenges faced by students in understanding physics concepts and calculations.
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I think i found the answers but the solutions don't make sense to me. Please help me correct my solution. Thanks!

A soccer ball is released from rest at the top of a grassy incline. After 6.3 seconds, the ball travels 51 meters. One second later, the ball reaches the bottom of the incline.
a) What was the ball's acceleration? (Assume that the acceleration was constant.)
b) How long was the incline?


a)
at rest t=0 and yi=0
at t=6.3 yf=51 m
yf-yi= vi(t)+1/2(a)(t)^2
51m=0(6.3)+1/2(a)(6.3 s)^2
[(51m)(2)]/39.69s^2=a=2.57 m/s^2

b)
a(constant)=2.57m/s^2
t(final)=7.3s

deltay=vi(7.3s)+1/2(a)(t)^2
deltay=0+1/2(2.57m/s^2)(7.3s)^2
deltay=68.5m
 
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kari82 said:
I think i found the answers but the solutions don't make sense to me. Please help me correct my solution. Thanks!

A soccer ball is released from rest at the top of a grassy incline. After 6.3 seconds, the ball travels 51 meters. One second later, the ball reaches the bottom of the incline.
a) What was the ball's acceleration? (Assume that the acceleration was constant.)
b) How long was the incline?


a)
at rest t=0 and yi=0
at t=6.3 yf=51 m
yf-yi= vi(t)+1/2(a)(t)^2
51m=0(6.3)+1/2(a)(6.3 s)^2
[(51m)(2)]/39.69s^2=a=2.57 m/s^2

b)
a(constant)=2.57m/s^2
t(final)=7.3s

deltay=vi(7.3s)+1/2(a)(t)^2
deltay=0+1/2(2.57m/s^2)(7.3s)^2
deltay=68.5m

Looks fine to me. Why do you think it doesn't make sense?
 
This is my first physics class (university physics) and I always feel like I'm missing something.. I like to have confirmation from someone that knows what they r doing ;-)

Can you give me a hint on question c please? Thanks!
 
kari82 said:
This is my first physics class (university physics) and I always feel like I'm missing something.. I like to have confirmation from someone that knows what they r doing ;-)

Can you give me a hint on question c please? Thanks!

Did you post a c) question? Did you post your attempt at a solution for whatever c) is?
 
Question c was in a different post.. I'm sorry! I made a mistake..
 
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