A 0.45 kg soccer ball changes its velocity by 20.0 m/s due to a force applied to it in 0.10 seconds. what force was necessary for this change in velocity?

90N

Explanation:

Mass of ball = 0.45 kg

Change in velocity = 20.0 m/s

Time = 0.10 seconds

Force required for change = ?

Since force refers to the change in momentum per unit time, hence

Force = Momentum / Time

i.e Force = Mass x (change in velocity / time)

Force = 0.45kg x (20.0m/s /0.10second)

= 0.45kg x (200 m/s^2)

= 90N

Thus, 90N of force was necessary for this change in velocity

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.