How Do You Calculate a Bird's Average Acceleration?

[christinaa_s]

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)

 

[topsquark]

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

 

[kyle8921]

Great job on solving the problem and calculating the average acceleration! Your calculations are correct and your method is sound. To answer your questions, yes, va and vb are the initial and final velocities, respectively. Also, the average acceleration is a vector quantity, so it should be expressed with both magnitude and direction, as you have done. Keep up the good work!