Answer:
new force is 6 times of the initial force.
Explanation:
Let the charges on two objects is q₁ and q₂. The electric force between charges is given by :

Objects 1 and 2 attract each other with a electrostatic force of 18.0 units
If the charge of Object 1 is doubled and the charge of object 2 is tripled, it means,
and
. New force is given by :

So, the new electrostatic force between objects will become 6 times of the initial force.
Option C
The fact that voltage can be created by exerting force on a crystal is used in Knock sensor
<u>Explanation:</u>
Any knock to an engine exhibits as a little shake that is distinguished by the knock sensor. This sensor acts by altering the fluctuation to an electrical sign, which is later transferred to the processor mastering the ignition system.
There the variation in quake to the voltage sign modifies the timing improvements on the kindling. The knock sensor is placed on the engine base, cylinder cap or consumption manifold. This is because its purpose is to sense fluctuations affected by engine knock or explosion.
Explanation:
Given that,
Electric field = 5750 N/C
Charge 
Distance = 5.50 cm
(a). When the charge is moved in the positive x- direction
We need to calculate the change in electric potential energy
Using formula of electric potential energy



Put the value into the formula


The change in electric potential energy is 
(b). When the charge is moved in the negative x- direction
We need to calculate the change in electric potential energy
Using formula of electric potential energy



Put the value into the formula


The change in electric potential energy is 
Hence, This is the required solution.
Answer:
Ratio of series current to parallel
= 1 : 8
Explanation:
Total resistance Rt
For series, Rt = 2+2+2+2 = 4ohms
For parallel, 1/Rt = 1/2 + 1/2 + 1/2 + 1/2
1/Rt = 4/2, Rt = 2/4 ohms.
If we use a 1V battery, then,
I = V/Rt
I = 1/4 = 0.25 ampere for series arrangement.
I = 1/0.5 = 2 ohms.
Ratio of current of series to parallel = 0.25 : 2
= 1 : 8