Answer:
when we lower a bucket into a well to fetch water, the work done by gravity is positive since force and displacement are in the same direction.
Explanation:
Answer:
10000 J or 10 KJ
Explanation:
power = workdone/time taken
400 = workdone/25
workdone = 400 * 25
=10000 J
the number of electrons that fill the outer shell determines the properties of elements
Answer:

Explanation:
Given that
The speed of the airplane ,v= 142 m/s
The speed of the air ,u = 30 m/s
Lets take angle make by airplane from east direction towards north direction is θ .
Now by using diagram ,we can say that

Now by putting the values in the above equation we get



Therefore the angle will be 12.19° .
Atoms, molecules, electrons, photons, protons etc.