<span>The bending of light rays by sun is twice in Einstein's theory as in Newton's theory of gravitation. Einstein's theory was verified by Eddington during the solar eclipse in 1919
Also observed precession of aphelion of mercury completely explained by Einstein's theory but not by Newtonian gravity</span>
Answer:
1. Static electricity has two charges magnetism has two poles.
2. Same charges and same poles repel and opposite charges and poles attract.
3. Static electricity is produced by charges(at rest) Magnetism is produced by charges(moving with uniform speed)
Explanation:
Given that,
Charge 1, 
Charge 2, 
The distance between charges, r = 1.99 m
To find,
The electrostatic force and its nature
Solution,
(a) The electric force between two charges is given by :



(b) As the magnitude of both charges is positive, then the force between charges will be repulsive.
Therefore, this is the required solution.
Answer:
Sound and light are similar in that both are forms of energy that travel in waves.
Explanation:
They both have properties of wavelength, freqency and amplitude. ... Sound can only travel through a medium (substance) while light can travel through empty space. Sound is a form of mechanical energy caused by vibrations of matter.
We have to use the equation speed=distance/time.
We want the average speed in second so we have to change the minutes into seconds. We can do this by multiplying the minutes by 60 (60seconds in 1 minute). 60x1.4= 84 seconds.
Speed=distance/time, distance is 82 and time is 84 so speed=82/84
Average speed = 0.98ms^-1 (2dp)