Question

(A.)

A hawk flies in a horizontal arc of radius
13.4 m at a constant speed of 4.5 m/s.
Find its centripetal acceleration.
Answer in units of m/s2.

(B.)
It continues to fly along the same horizon-
tal arc but increases its speed at the rate of
1.45 m/s2.
Find the magnitude of acceleration under
these new conditions.
Answer in units of m/s2.

Answer 1

acceleration = V^2/R in both cases

Put the radius R in meters and the speed in m/s and you will get m/s^2 units for the answer.

Answer 2

yes i understand A but in B it's increasing the speed at a rate (which means acceleration) of 1.45 m/s^2 and that's where i get lost

Answer 3

Yes, I neglected to notice that V is increasing in (B)

When the acceleration starts, V is the original 4.5 m/s value, and you introduce a new tangential acceleration of 1.45 m/s^2. The centripetal acceleration starts at V^2/R = 1.51 m's^2

The magnitude of the acceleration starts at
sqrt[(1.45)^2 + (1.51)^2] = 20.9 m/s^2, and keeps increasing

Answer 4

thank you so much!!!

Answer 5

I missed a decimal point in doing the final calculation. It should be 2.09 m/s^2.

Answer 6

what is the first anwser? (A)

Answer 7

the first answer is 1.51 because you do (4.5)^2/ 13.4.