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
Answer:


Explanation:
Given
--- Ken's share
Required
The fraction each got
Since they both shared a cake, we have:

Substitute: 

Factorize


Divide both sides by 3

Recall that: 


'Displacement' is the distance and direction between the starting point and
ending point, regardless of the path followed to get there.
A particle that's executing simple harmonic motion is always in the same place
where it was one time period ago, and where it will be later after another time
period has passed.
So its displacement during exactly one time period is exactly zero.