Assuming all objects are moving with the same velocity, which statement describes the object with the smallest inertia?
a. a driver continues forward after his car takes a sharp turn.
b. a bowling ball rolls across a street and into a large soccer field.
c. a pebble is thrown in space and continues in a straight line.
d. an avalanche of snow falls down a steep mountain side.

C. A pebble is thrown in space and continues in a straight line.

Explanation:

Here it is given that the property of inertia is totally depends on the mass of the object.

Here it is given that all the objects given here is moving with same speed

So here the speed will be same and we need to find the correct statement which will have least inertia.

So smallest inertia is corresponding to the smallest mass

So here we can say that the correct answer will be

C. A pebble is thrown in space and continues in a straight line.

Because rest other given examples are of more mass due to which they all have more inertia then pebble.

Also inertia does not depends on the speed so correct answer is as stated above

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.