A crewman on the starship Enterprise is on shore leave on a distant planet. He drops a rock from the top of a cliff and observes that it takes 3.00 s to reach the bottom. He now throws another rock vertically upwards so that it reaches a height of 2.00 m before dropping down the cliff face. The second rock takes 4.12 s to reach the bottom of the cliff. The planet has a very thin atmosphere that offers negligible air resistance. (a) How high is the cliff? (b) What is the value of g, the acceleration due to gravity, on the planet?(adsbygoogle = window.adsbygoogle || []).push({});

Here's how I did this:

2 + h = whole height which took 4.12 seconds

2+h = .5a(4.12)^2

h= 8.4872a - 2

h= .5a(3)^2

h= 4.5a

8.4872a-2 = 4.5a

a= .5 m/s^2

h=4.5a

h= 4.5(.5)

h= 2.257 m

Can anyone PLEASE verify these answers? Thanks a lottt

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# Homework Help: A crewman throws a rock

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