# Recent content by Matthew T

1. ### If a conductor gets an induced charge is then grounded

As Simon says: if the charged object which is inducing the separation of charge on the neutral conductor is negatively charged and you briefly ground the neutral conductor on the side furthest away from the charged object, the conductor will then have a net positive charge. If the charged object...
2. ### Newton's Second Law assumptions

Newton, in relation to his theory of gravitation, commented on the 'absurdity of instantaneous action at a distance', so even though he couldn't think in terms of velocity of energy transmission, there is evidence that he thought in terms of velocity of force transmission. So Newton proposed it...
3. ### Newton's Second Law assumptions

First of all, many thanks to you and Chi Meson for confirming the identified assumptions in the 2nd Law. I agree that wave theory is needed to model the 'steel rod' scenario. To calculate the extra force applied, I assumed that the velocity of sound stayed constant (despite the changes in...
4. ### Newton's Second Law assumptions

Hi Sophie, the form that you and Chi Meson are describing waits for the transient to settle into a steady state. Chi Meson then identifies the crux of the issue-the transient. Say a bullet is travelling faster than the speed of sound in lead. When it impacts, the back half doesn't know that the...
5. ### Newton's Second Law assumptions

Interesting. Reminds me of the Heaviside eqns being labelled Maxwell's eqns. Euler's form does make the assumption of instantaneous transmission of force more obvious, and more to the point it is the form most commonly taught/used. I take it that you are not convinced that there is an...
6. ### Newton's Second Law assumptions

Hi people Newton's Second Law a=F/m assumes that either a body is pointlike or that force is transmitted instantaneously across it. Special relativity which applies to Newton's First Law and which was developed from the assumption of a finite velocity of energy transmission, has enjoyed...