Calculating Time and Velocity of a Falling Object

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A chipmunk drops an acorn from a height of 6.0 m, and the calculations for the time in the air and final velocity were discussed. The time calculated was approximately 1.1 seconds, and the final velocity was initially found to be 10.78 m/s. However, it was noted that rounding the time before calculating velocity led to a slight inaccuracy. The correct final velocity, when calculated without premature rounding, is 10.84 m/s, which should be rounded to 11 m/s for consistency with the significant figures of the original data. Accurate calculations and proper rounding are crucial for precise results in physics problems.
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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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