<h2>
Answer:Third</h2>
Explanation:
Newton's third law states that every action force has a equal and opposite reaction force.
Example 1:
Consider yourself hitting a wall with your hand,you are exerting a force on the wall but still you feel hurt because the wall exerts same force on your hand in opposite reaction.
Example 2:
Consider yourself standing on ground.You are exerting force on ground.But how are you able to stand on ground even if your mass is forcing you to go down?The answer is normal reaction force.The ground exerts a force on your feet which makes you to stand still.
Luxury is an antonym of necessity. Necessity is an antonym of luxury.
As nouns the difference between necessity and luxury is that necessity is the quality or state of being necessary, unavoidable, or absolutely requisite while luxury is very wealthy and comfortable surroundings.
Answer:
0.005 m
Explanation:
length of steel (L°) = 12 m
initial temperature (T) = 16 degrees
expected temperature (T') = 50 degrees
We can find how large the gaps should be if the track is not to buckle when the temperature is as high as 50 degrees from the formula below
ΔL = ∝L°ΔT where
- ΔL = expansion / gap
- ∝ = linear expansion coefficient of steel =
- L° = initial length
- ΔT = change in temperature
ΔL = 
x 12 x (50-16) = 0.005 m
