Scientists have investigated how quickly hoverflies start beating their wings when dropped both in complete darkness and in a lighted environment. starting from rest, the insects were dropped from the top of a 40-cm-tall box. in the light, those flies that began flying 200 ms after being dropped avoided hitting the bottom of the box 80% of the time, while those in the dark avoided hitting only 22% of the time.
a. how far would a fly have fallen in the 200 ms before it began to beat its wings?
b. how long would it take for a fly to hit the bottom if it never began to fly? in seconds.

Answers:

A) 0.204 m

B) 0.285 s

Explanation:

This described situation is free fall, this means the initial velocity of the fly is zero, and the equation that will be used is:

(1)

Where:

is the final height of the fly

is the initial height of the fly

is the initial velocity of the fly

is the time

is the acceleration due to gravity

(2)

(3)  This is the distance at which the fly would begin to beat its wings

In this part we will also use equation (1), but we will find the time:

(1)

Where:

is the final height of the fly

is the initial height of the fly

is the initial velocity of the fly

is the time  we need to find

is the acceleration due to gravity

(4)

Isolating :

(5)

(6)  This is the time it would take for a fly to hit the bottom of the box

answer: the rock sample is a sedimentary rock.

explanation:

it is given that:

mass of rock sample, m = 2.7 g

volume of rock sample,

so, density of rock sample will be

since, the density of rock sample is . hence, the rock sample is a sedimentary rock, whose densities varies between .