Use the impulse-momentum theorem to find how long a stone falling straight down takes to increase its speed from 5.6 m/s to 10.6 m/s . express your answer in seconds.

As stated, the impulse and momentum definitions will be used to later find the value of time through the force of gravity. According to the theory, the impulse formula is given as,

Here,

F = Force

Change in time

Now using the impulse theorem we have that,

Change in Impulse = Change in momentum

(1)

The change in momentum is given as

The force due to gravity is through the Newton's second law

Here,

m = mass

g = Acceleration due to gravity

Substitute the value in (1)

Therefore it will take 0.51s.

D. The position of the first quarter moon and third quarter moon have been interchanged.    

Explanation:

Phases of moon are the shapes of illuminated portion of the moon that is visible from the earth.

New moon occurs when the moon comes between the earth and the sun. The lit portion faces away from the earth.

After new moon, waxing crescent phase occurs followed by first quarter. In the first quarter, half moon is visible.

Waxing gibbous occurs which is when more than half and less than full face of the moon is visible. This is followed by full moon when earth comes between moon and the sun.

The waning gibbous phase is visible for next few days till the third quarter phase. Then waning crescent phase and finally new moon again.

In the given diagram made by Melanie, the position of first quarter and third quarter are wrong and must be interchanged.