A large boulder is ejected vertically upward from a volcano with an initial speed of 40.1 m/s. (Air resistance can be ignored.)(adsbygoogle = window.adsbygoogle || []).push({});

a) At what time after being ejected is the boulder moving at 19.2 m/s upward? (g = 9.80 m/s^2)

b) At what time is it moving at 19.2 m/s downward? (g = 9.80 m/s^2)

c) When is the displacement of the boulder from its initial position zero? g = 9.80 m/s^2

d) When is the velocity of the boulder zero? g = 9.80 m/s^2

I did and understand these four parts. Now the following two parts are the ones I do not understand.

e) What is the magnitude of the acceleration while the boulder is moving? (Take g = 9.80 m/s^2 for free fall acceleration)

Well, the boulder can move up or down, but is the magnitude 9.80 m/s^2 for both scenarios?

f. What is the direction, up or down, of the acceleration while the boulder is moving?

Won't the direction be down?

Thanks for any help.

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# Homework Help: Acceleration and Moving Objects

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