convex lenses.
eyeglasses with convex lenses increase refraction, and accordingly reduce the focal lenght
Answer:
18 m
Explanation:
G = Gravitational constant
m = Mass of planet = 
= Density of planet
V = Volume of planet assuming it is a sphere = 
r = Radius of planet
Acceleration due to gravity on a planet is given by

So,

Density of other planet = 
Radius of other planet = 

Since the person is jumping up the acceleration due to gravity will be negative.
From kinematic equations we have

On the other planet

The man can jump a height of 18 m on the other planet.
The best demonstration that applies to Newton's Third Law of motion would be D) When you walk your foot pushes down on the ground while the ground pushes back on your foot.
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Newton's Third Law states that for every action, there is an equal and opposite reaction. This is actually explains that forces come in pairs and forces are an interaction between two objects. As per the correct option given in the question explains Newton’s Third Law.
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When you walk your foot (say object A) pushes down on the ground while the ground (say object Q) pushes back on your foot with the same force but in the opposite direction.
Answer:
Astronomer Edmond Halley
Explanation:
The astronomical unit using the transit of venus
The underlying principle behind Halley's method is called parallax