Question

If you accelerate a particle to the speed of light and keep it accelerated there, what will happen to its mass?

Answer 1

According to the theory of special relativity, as an object with mass accelerates and approaches the speed of light, its relativistic mass increases. This phenomenon is known as "mass increase with velocity" or "relativistic mass."

The equation that relates the relativistic mass ($m^{\prime }$) of an object to its rest mass ($m_0$) and its velocity ($v$) is given by:

$m^{\prime }=\frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}$,

where $c$ is the speed of light in a vacuum.

As the velocity of the particle approaches the speed of light ($v\to c$), the denominator in the equation approaches zero, and therefore the relativistic mass ($m^{\prime }$) increases without bound. However, it is important to note that no massive object with rest mass can reach or exceed the speed of light, as it would require an infinite amount of energy.

The concept of relativistic mass is often less emphasized in modern physics, and instead, the concept of relativistic energy ($E$) and momentum (pp<span class="strut" style="height: 0.625em; vertical-ali