Question

For Extraordinary people.

Mass is always constant but if an object is moving with a speed equal to the speed of light, then the mass increases. How?

And explain in easiest way.

Answer 1

hey mate

here is your answer

according to the quantative equation of mass

the mass of a body moving with a velocity v is given by:

mv=m0/(√(1-v²/c²))

where m0 =mass of the body at rest
c=speed of the light (constant here)
v=velocity of the body

actually, the mass of the body changes which the change in the velocity.HOWEVER, THIS CHANGE COMES TO OUR NOTICE ONLY WHEN THE SPEED OF THE BODY REACHES CLOSE TO THE SPEED OF THE LIGHT.

Answer 2

In my opinion, when the object is at rest its mass can not be changed because the object is at rest at that time and when it is travelling with the speed of light (i.e.,c=3×10^8 ) the mass of the object is decreases.

Now I proved that:-

Let us an example to prove that the mass of the object is decreases when it is travelling with light speed.

Suppose that a train which is running like as a speed of light (i.e.,c=3×10^8) and an object of mass 10kg is kept on the train but when the train is at rest the mass of the object is constant i.e.10kg and when the train is running with the speed of light (i.e.,c=3×10^8).

Now, given in these,

Mass of the object=10kg

Speed of light(c)=3×10^8.

Then,the Kinetic Energy (K.E) of the body is,

Kinetic energy=1/2×mv^2=1/2×10×(3×10^8)^2=5×9×10^16=45×10^16 joule

On putting this value of K.E in Einstein formula E=mc^2, we have

E=mc^2

45×10^16=m×(3×10^8)^2

45×10^16=m×9×10^16

45×10^16÷9×10^16=m

5×1=m

m=5kg

It implies that when a object is travelling with the speed of light its mass is decreases or

mass is become half of its intially mass.