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a rock is thrown upward with a velocity of 21 meters per second from the top of a 44 meter high cliff, and it misses the cliff on the way back down. when will the rock be 5 meters from the water, below? round your answer to two decimal places.

The answer to your question is: t = 3.54 s

Step-by-step explanation:

data

vo = 21 m/s

height of the cliff = 44 m

t= ? when the rock be 5 meters from the water.

Process

First, calculate the distance the rock reach in its way up.

    h max = vo² /2g = (21)² / 2(9.81) = 22.5 m

total height = 44 m + 22.5 m = 66.5 m

but we need to calculate the time when the rock be 5 m from the water so,

    height = 66.5 - 5 m

   height = 61.5 m

Now, use free fall formulas to calculate time

   h = gt² / 2

   61.5 = (9.81)t² / 2

solve for t

  2(61.5) = 9.81t²

   123   = 9,81t²

   t² = 123 / 9.81

   t² = 12.53

     t = 3.54 s

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.