If energy and mass are interchangeable, how are they in the same equation. Like in the work energy therum one? If energy and mass are interchangeable, how are they in the same equation. Like in the work energy therum one? Solution In any equation every term should have same unit. For example work energy theorem in this theorem every term has unit of energy that is J Change in kinetic energy = Work done (1/2)mV f 2 - (1/2)mV i 2 = work done Here mass is accomplished with the velocity which makes the complete term as kg*(m/s) 2 = kg*(m/s 2 )*m = Nm = J Hence each and every term in this equation is of energy. That means mass and energy are interchangeable but mass will have energy only when it is in motion. If mass is at rest than it will not have any energy. .

1. If energy and mass are interchangeable, how are they in the same equation. Like in the work
energy therum one?
If energy and mass are interchangeable, how are they in the same equation. Like in the work
energy therum one?
Solution
In any equation every term should have same unit.
For example work energy theorem in this theorem every term has unit of energy that is J
Change in kinetic energy = Work done
(1/2)mV f
2
- (1/2)mV i
2
= work done
Here mass is accomplished with the velocity which makes the complete term as kg*(m/s) 2
=
kg*(m/s 2
)*m = Nm = J
Hence each and every term in this equation is of energy.
That means mass and energy are interchangeable but mass will have energy only when it is in
motion.
If mass is at rest than it will not have any energy.