Convection can best be observed as she blows the warm steam air that rises.
As the warm steam rises, she forces displaces it with cool air from her mouth. Because the warm steam is less dense it rises and because the cool air is more dense, it displaces the warm air.
This scenario is an example of convection.
There are two possibilities for this question:
1- The shopping cart is at rest (not moving):
In this case:
∑Forces = 0
Force exerted by Jim + Force exerted by cart = 0
2 + Force exerted by cart = 0
Force exerted by cart = -2
2- The cart is moving as a result of a net force "m":
In this case:
∑Forces = m
Force exerted by Jim + Force exerted by cart = m
Force exerted by cart = m-2
Answer:
The compression of the spring is 24.6 cm
Explanation:
magnitude of the charge on the left, q₁ = 4.6 x 10⁻⁷ C
magnitude of the charge on the right, q₂ = 7.5 x 10⁻⁷ C
distance between the two charges, r = 3 cm = 0.03 m
spring constant, k = 14 N/m
The attractive force between the two charges is calculated using Coulomb's law;

The extension of the spring is calculated as follows;
F = kx
x = F/k
x = 3.45 / 14
x = 0.246 m
x = 24.6 cm
The compression of the spring is 24.6 cm