Answer:
<em>The penny will hit the ground at 6.39 seconds</em>
Explanation:
<u>Free Fall</u>
The penny is dropped from a height of y=200 m. The equation of the height on a free-fall motion is given by:

Where
, and t is the time.
Solving for t:

Using the value y=200:

t=6.39 sec
The penny will hit the ground at 6.39 seconds
Answer:
Statement A is greater than Statement B.
Explanation:
Statement A: 2.567 km, to two significant figures..
To 2 sig figures means only 2 whole numbers should be left after approximation. Thus, 2.567 to 2 significant figures is 2.6 km
Statement B: 2.567 km, to three significant figures. To 3 sig figures means only 3 whole numbers should be left after approximation. Thus, 2.567 to 3 significant figures is 2.57 km
Comparing both values, statement A is obviously greater than Statement B
Answer:
I will answer this in English, we can translate it to:
Why if you charge a mate by an amount of time you are not doing work?
This happens because work is defined as the displacement done by a force:
W = d*F
where W is work, d is the distance, and F is the force.
This means that the amount of time that you are charging your mate does not affect the mechanical work, the only time that you are doing work is when you are lifting him.
Answer:
Part a)

Part b)

Explanation:
Part a)
Electric potential is a scalar quantity
so here we can say that total potential due to a ring on its center is given as

here we know that



now we have


Part b)
Potential on the axis of the ring is given as


