Einstein's energy mass equivalence relation say that if the whole given mass is converted to energy then it would be

where
m = mass in kg
c = speed of light in m/s
this is the origination of quantum physics and by this formula we can relate the dual nature of light and particle
So correct relation above will be

Answer:

Explanation:
Electric field in a given region is given by equation

as we know the relation between electric field and potential difference is given as

so here we have


here we know that
and 
so we will have

so we will have

Answer:
Explanation:
Speed is defined as the rate at which an object covers a particular distance. So the formula for determining speed is given as the ratio of distance to time taken for covering that distance.
Speed = Distance/Time
As here the distance is given in km units and time in s units, so the units of any one parameter should be changed. Since we know that speed of sound is always about 300 m/s. So it is better to convert the unit of distance from km to m.
Hence, now the distance traveled by the noise is 2000 m and time taken is 5.8 s.
So the speed of noise = Distance/Time = 2000/5.8=345 m/s.
Thus, the speed of noise is slightly greater than the speed of sound and it is found to be 345 m/s.
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