Calculating Time and Velocity of a Falling Object

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The discussion focuses on calculating the time and velocity of a falling object, specifically an acorn dropped by a chipmunk from a height of 6.0 meters. The initial conditions include an acceleration due to gravity of 9.8 m/s² and an initial velocity of 0 m/s. The calculated time in the air is approximately 1.1 seconds, and the velocity upon impact is calculated to be 10.78 m/s. However, it is noted that the velocity should be rounded to two significant figures, resulting in a final velocity of 11 m/s.

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A chipmunk drops an acorn from a branch 6.0 m above the ground.
a) How long is it in the air?
b)How fast is it going when it hits the ground?


I decided my given was
a=9.8m/s2
d= 6.0 m
vi= 0 m/s

So I used the distance formula (d=vi+1/2*a*t2) and solved for time. I got about 1.1 s.
For the next part I used vf=vi*t+a*t and solved.

I got
a)1.1 seconds
b) 10.78 m/s

Is this correct?
 
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C42711 said:
A chipmunk drops an acorn from a branch 6.0 m above the ground.
a) How long is it in the air?
b)How fast is it going when it hits the ground?


I decided my given was
a=9.8m/s2
d= 6.0 m
vi= 0 m/s

So I used the distance formula (d=vi+1/2*a*t2) and solved for time. I got about 1.1 s.
For the next part I used vf=vi*t+a*t and solved.

I got
a)1.1 seconds
b) 10.78 m/s

Is this correct?

Method good, but the fact you rounded off the time before calculating velocity is not desirable. Without rounding the vel calculates to 10.84

Given that orignal data was to 2 figures only, the velocity should be rounded to 2 figures, which will give 11 in both cases. You even get the same result if you stretch to 3 figures - 10.8, but if you quote 4 figures; 10.78 is incorrect.
 
Thank you so much! Highly appreciated.:)
 

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