Question

A bird flies north at 20 `ms^-1` for 15second and then flies west at `25ms^-1` for 10second. Find the average acceleration for the whole trip. Solution???

Answer 1

Average acceleration: `color(red)0`

Explanation:

Assuming the bird started at rest and stopped flying (returned to rest) at the end of its flight, any positive acceleration would need to be balanced by negative acceleration.

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It is entirely possible (maybe likely) that this question should have asked for the average velocity.

In this case the bird flew 300 m North and 250 m W over a period of 25 seconds;
or on average 12 m North and 10 m West per second
for an average of (using the Pythagorean Theorem)
`color(white)("XXX")sqrt(12^2+10^2)` m/sec
at an angle of
`color(white)("XXX") arctan(10/12)` West of North