Kinetic Energy and Mass for Slow Particles

Kinetic Energy and Mass for Slow Particles - Kinetic Energy...

This preview shows pages 1–2. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Kinetic Energy and Mass for Slow Particles Recall that to get momentum to be conserved in all inertial frames, we had to assume an increase of mass with speed by the factor This necessarily implies that even a slow- moving object has a tiny mass increase if it is put in motion . How does this mass increase relate to the kinetic energy? Consider a mass m , moving at speed v , much less than the speed of light. Its kinetic energy E =½ m v ², as discussed above. Its mass is which we can write as m 0 + dm, so dm is the tiny mass increase we know must occur. It’s easy to calculate dm . For we can make the approximations So, for Again, the mass increase dm is related to the kinetic energy KE by KE = ( dm ) c 2 . Having looked at two simple cases, we’re ready to derive the general result, valid over the whole range of possible speeds. Kinetic Energy and Mass for Particles of Arbitrary Speed We have shown in the two sections above that (in the two limiting cases) when a force does work...
View Full Document

{[ snackBarMessage ]}

Page1 / 2

Kinetic Energy and Mass for Slow Particles - Kinetic Energy...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online