Charges a and b in the figure are equal. each charge exerts a force on the other of magnitude
f. suppose the charge of b is increased by a factor of 4, but everything else is unchanged.

The formula used to determine the force between two charges is
F = kQ1Q2/d2
The first has a and b with equal charges
F = k q q /d2
F = kq2/d2
In the second scenario, the charge of b is increased by 4
F = k q 4q /d2
F = 4kq2/d2
This means that increasing the charge by 4 also increases the force between  them by 4.

Earthplanet yplanet y5=earth     *many different equationsplanet x1.5=earthplanet x is two times planet yobject 5,2500 mass5,1,3,2,4object 1 is four times obect 4