Question

Problem 2

Answer 1

Given information

A car that is travelling along the -axis. The direction and speed are different in all the five cases mentioned in the question. We are asked to find in which of the given cases, the car has a negative velocity and a positive acceleration.

Step-by-step explanation

Step 1.

When the car moves in the negative direction, it has a negative velocity. So, the car is moving in the direction. If the object is speeding, we can say that the acceleration vector is directed along the direction of motion.

So, here, if the car is speeding, its acceleration is directed in the same direction as that of the velocity. But velocity here is negative, so the acceleration will also be negative.

If the car is slowing down, the acceleration is directed opposite to that of its motion, i.e.; velocity. So, acceleration is negative of negative, that is, positive.