Answer:
Power_input = 85.71 [W]
Explanation:
To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.

where:
W = work [J] (units of Joules)
F = force [N] (units of Newton)
d = distance [m]
We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.
Now replacing:
![W = (80*10)*3\\W = 2400 [J]](https://tex.z-dn.net/?f=W%20%3D%20%2880%2A10%29%2A3%5C%5CW%20%3D%202400%20%5BJ%5D)
Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.

where:
P = power [W] (units of watts)
W = work [J]
t = time = 40 [s]
![P = 2400/40\\P = 60 [W]](https://tex.z-dn.net/?f=P%20%3D%202400%2F40%5C%5CP%20%3D%2060%20%5BW%5D)
The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.
![Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W]](https://tex.z-dn.net/?f=Effic%3D0.7%5C%5CEffic%3DP_%7Brequired%7D%2FP_%7Bintroduced%7D%5C%5CP_%7Bintroduced%7D%3D60%2F0.7%5C%5CP_%7Bintroduced%7D%3D85.71%5BW%5D)
Spring tides will occur during a full moon and an new moon. The sun and moon are on a certain angle causing these tides to be neap tides, they aren't high tide nor are they low tides so you would verbalize they are in between and that is why it is called neap tides as well.
For 2 draw the molucules very close together. because in soilds the molucules are VERY close to gether.
and for 3 Draw them with a lot of space apart from each other. Molucules move freely and openly in air and space.
Hope this helps! Please mark as brainliest! Thanks!! :D
That would be <span>the national chairperson
-I hope this helped.</span>
The radial velocity method preferentially detects large planets close to the central star
- what is the Radial velocity:
The radial velocity technique is able to detect planets around low-mass stars, such as M-type (red dwarf) stars.
This is due to the fact that low mass stars are more affected by the gravitational tug of planets.
When a planet orbits around a star, the star wobbles a little.
From this, we can determine the mass of the planet and its distance from the star.
hence we can say that,
option D is correct.
The radial velocity method preferentially detects large planets close to the central star
Learn more about radial velocity here:
<u>brainly.com/question/13117597</u>
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