Explanation:
initial velocity= 80km/hr = 22.22 m/s
distance= 40m
Final velocity= 0m/s ( as it needs to be stopped)
<u>Using </u><u>third </u><u>equation </u><u>of </u><u>motion</u><u>,</u>
=> 2as = v² - u²
=> 2a * 40m = 0² - (22.22 m/s)²
=> a = - 493.72/80 m/s²
=> a = - 6.17m/s²
<u>Using </u><u>first </u><u>equation </u><u>of </u><u>motion</u><u>,</u>
=> a = v - u /t
=> -6.17 = 0-22.22/t
=> t = -22.22/-6.17 s
=> t ≈ 3.7 s = stopping time
All answers to the Earth Science, Meteorology: Part 1 Unit Test
1. B. March 21
2. D. December 21
3. B. They move faster.
4. C. 300,000 kilometers per second
5. B. Conduction
6. A. longer than those emitted by the sun
7. D. Water vapor and carbon dioxide
8. C. Scattering
9. D. Both b and c
10. C. There is a greater percentage of water surface in the Sourhern Hemisphere
11. D. Both a and b
12. B. Absorbing outgoing radiation
13. D. Deposition
14. B. It contains more water vapor than cold air
15. D. Both a and b
16. D. All of the above
17. B. Subtropical high
18. B. Day and flows torad the land
19. Essay
20. Essay
21. Essay
22. Essay
Answer:
The air resistance on the skydiver is 68.6 N
Explanation:
When the skydiver is falling down, there are two forces acting on him:
- The force of gravity, of magnitude
, in the downward direction (where m is the mass of the skydiver and g is the acceleration due to gravity)
- The air resistance,
, in the upward direction
So the net force on the skydiver is:
![F=mg-R](https://tex.z-dn.net/?f=F%3Dmg-R)
where
m = 7.0 kg is the mass
![g=9.8 m/s^2](https://tex.z-dn.net/?f=g%3D9.8%20m%2Fs%5E2)
According to Newton's second law of motion, the net force on a body is equal to the product between its mass and its acceleration (a):
![F=ma](https://tex.z-dn.net/?f=F%3Dma)
In this problem, however, the skydiver is moving with constant velocity, so his acceleration is zero:
![a=0](https://tex.z-dn.net/?f=a%3D0)
Therefore the net force is zero:
![F=0](https://tex.z-dn.net/?f=F%3D0)
And so, we have:
![mg-R=0](https://tex.z-dn.net/?f=mg-R%3D0)
And so we can find the magnitude of the air resistance, which is equal to the force of gravity:
![R=mg=(7.0)(9.8)=68.6 N](https://tex.z-dn.net/?f=R%3Dmg%3D%287.0%29%289.8%29%3D68.6%20N)
Answer:
B
Explanation:
In a solution, one part has to dissolve into the other.
Answer:
<h2>0.67 m/s²</h2>
Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
![a = \frac{f}{m} \\](https://tex.z-dn.net/?f=a%20%3D%20%20%5Cfrac%7Bf%7D%7Bm%7D%20%20%5C%5C%20)
f is the force
m is the mass
From the question we have
![a = \frac{2}{3} \\ = 0.66666...](https://tex.z-dn.net/?f=a%20%3D%20%20%5Cfrac%7B2%7D%7B3%7D%20%20%5C%5C%20%20%3D%200.66666...)
We have the final answer as
<h3>0.67 m/s²</h3>
Hope this helps you