Average intensity of electromagnetic wave is given by
I= (speed of light*permittivity*sq. electric field)/2
Speed of light = 3x10^8 m/s
Permittivity = 8.85x10^-12
Therefore,
Electric field = sqrt (2I/ (speed of light xpermittivity)) = sqrt ((2*4.50)/(3*10^8*8.85*10^-12)) = 58.22 V/m
Answer : The correct option is, (d) 4 times
Solution :
According to the Coulomb's law, the electrostatic force of attraction or repulsion between two charges is directly proportional to the product of the charges and is inversely proportional to the square of the distance between the the charges.
Formula used :
where,
F = electrostatic force of attraction or repulsion
= Coulomb's constant
and 
are the charges
r = distance between two charges
First we have to calculate the force exerted between S and q when the distance between the charge is 1 unit and let us assumed that the charge be 'q'
..........(1)
Now we have to calculate the force exerted between S and p when the distance between the charge is 2 unit at the same charge.
...........(2)
Equation equation 1 and 2, we get
Therefore, the force exerted between S and q is 4 times the force exerted between S and p.
Answer:
The number of crates is 84580.
Explanation:
mass, m = 30 kg
height, h = 0.9 mm
Power, P = 0.5 hp = 0.5 x 746 W = 373 W
time, t = 1 minute = 60 s
Let the number of crates is n.
Power is given by the rate of doing work.
acceleration equals to the force applied divided by mass
an object moving at a velocity of x carries the force of its mass times its speed.
when you apply a force onto an object, the increase in speed of it would be affected by its mass. Think of it this way: you apply some force onto an iron ball, and apply the same force on a plastic ball (they are of equal volume). Which one moves faster, and which one moves slower? The answer is obvious: the iron ball will accelerate slower and travel slower, while the plastic ball is faster.
The iron ball has a greater mass, so the force which makes it accelerate is deduced more. The plastic ball has a smaller mass, so the force applied is divided by a smaller number.
I hope this helps you a bit.
Answer:
a bowling ball placed on the top shelf of a closet.
Explanation:
Potential energy is the energy that is stored in an object due to its position relative to some zero position. An object possesses gravitational potential energy if it is positioned at a height above (or below) the zero height.
Mathematically,
Potential energy, PE = M × g × h
