<span>A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds; or through the sharing of electrons as in covalent bonds.
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Answer:Same magnitude
Explanation:
When ball is dropped from shoulder height h then velocity at the bottom is given by

if it makes elastic collision then it will acquire the same velocity and riser up to the same height
If m is the mass of ball then impulse imparted is given by


Thus impulse imparted by gravity and Floor will have same magnitude of impulse but direction will be opposite to each other.
A decrease in it's operating temperature would make a heat engine less efficient. This is because in order to operate, a heat engine needs to be hot and maintain that temperature.
Answer:
The work done on the box is 80 J.
Explanation:
Given that,
Weight of box = 40 N
Distance = 2 meter
We need to calculate the work done
Using formula of work done


Where, x = distance
mg = weight
Put the value into the formula



Hence, The work done on the box is 80 J.