# Help needed with average acceleration question

QUESTION=
a bird takes 8.5 s to fly from position A to position B along the path. determine the bird's average acceleration.

va= 4.4 m/s (3 degrees S of E) -- is this the initial velocity?
vb= 7.8 m/s ( 25 degrees N of E) -- is this the final velocity?

THIS IS WHAT I GOT SO FAR, I"M NOT SURE IF IT IS RIGHT AT ALL -->

ay = vfy - vfi / time

i found , ax = 0.52
ay = 0.92

a(2) = ax(2) + ay(2)
= (0.52)2 + (0.92)2
= 0.29 + 0.85
= √1.14 m/s(2)
therefore, average acceleration = 1.07 m/s

tan = 0.92 \ 0.52
tan = 60.4 degrees

Therefore the average acceleration of the car is 1.07 m/s (60.4 degreesN of E)

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christinaa_s said:
QUESTION=
a bird takes 8.5 s to fly from position A to position B along the path. determine the bird's average acceleration.

va= 4.4 m/s (3 degrees S of E) -- is this the initial velocity?
vb= 7.8 m/s ( 25 degrees N of E) -- is this the final velocity?

THIS IS WHAT I GOT SO FAR, I"M NOT SURE IF IT IS RIGHT AT ALL -->

ay = vfy - vfi / time

i found , ax = 0.52
ay = 0.92

a(2) = ax(2) + ay(2)
= (0.52)2 + (0.92)2
= 0.29 + 0.85
= √1.14 m/s(2)
therefore, average acceleration = 1.07 m/s

tan = 0.92 \ 0.52
tan = 60.4 degrees

Therefore the average acceleration of the car is 1.07 m/s (60.4 degreesN of E)
Just a quick comment: You somehow got your acceleration components wrong. I get ax = 0.314733 /s^2 and ay = 0.360723 m/s^2. (That's with E being the +x and N being the +y.) Perhaps you should show how you are putting the numbers into the equations.

-Dan