The equipotential surfaces are the surface on which the electric potential is same. The work done in moving a charge from one point to another on an equipotential surface is always zero.

The electric field lines are always perpendicular to the equipotential surface.

$dV = \overrightarrow{E} . d\overrightarrow{r}\\\\$

For equipotential surface, dV = 0 so

$0 = \overrightarrow{E} . d\overrightarrow{r}\\\\$

The dot product of two non zero vectors is zero, if they are perpendicular to each other.

5 0

2 years ago

How can Newton's laws be applied to protect a smartphone screen during a collision?

Sonja [21]

smartphones break due to forces acting on the material.

force causes material to deform.

material is often brittle and cracks due to a limit on hardness / electricity in screens.

newton's 2nd law states

force = DV / DT

to help phones we must slow down change in momentum to reduce the force

thus we must use some form of damping in the form of a case .

the case is typically able to deform and rubber is elastic converting the kinetic energy to heat as it deforms instead of transferring it through the screen.

therefore the change in velocity occurs over a longer time. therefore the impulse decreases

7 0

3 years ago