This question can be answered with the basic laws of motion. Since the question is asking for FORCE, we
know we must need this equation:
Since we know m but don't know a, we must find it using another equation. The one to use is:
where
= the
change in velocity. In this case the change comes out
negative since the car is slowing down, and, you will notice that your answer will be a negative number to reflect this.
Leave the negative symbol in your answer. Now that you have a, simply solve for F above using F = m x a.