Answer:
a) t = 4.14 s
b) Speed with which it hits the ground = 40.58 m/s
Explanation:
Using the equations of motion,
g = 9.8 m/s², y = H = 84 m,
Initial velocity, u = 0 m/s,
final velocity, v = ?
Total Time of fall, t = ?
a) y = ut + gt²/2
84 = 0 + 9.8t²/2
4.9t² = 84
t² = 84/4.9
t = 4.14 s
b) v = u + gt
v = 0 + (9.8 × 4.14)
v = 40.58 m/s
Answer: it reduces dependence on fossil fuels. Disadvantage: it would emit pollution into the air.
This is a uniform rectilinear motion (MRU) exercise.
To start solving this exercise, we obtain the following data:
<h3><u>
Data:</u></h3>
- v = 4.6 m/s
- d = ¿?
- t = 10 sec
To calculate distance, speed is multiplied by time.
We apply the following formula: d = v * t.
We substitute the data in the formula: the <u>speed is equal to 4.6 m/s,</u> the <u>time is equal to 10 s</u>, which is left as follows:


Therefore, the speed at 10 seconds is 46 meters.

When the sun's rays strike Earth's surface near the equator, the incoming solar radiation is more direct (nearly perpendicular or closer to a 90˚ angle). Therefore, the solar radiation is concentrated over a smaller surface area, causing warmer temperatures.