Car moving on a straight road is an example of _________ motion.

rectilinear

The correct answer is option 3. rectilinear.

Rectilinear motion, also known as linear motion, refers to the motion of an object along a straight path. In rectilinear motion, the object moves in a single dimension, typically along a straight line, without changing its direction. When a car moves on a straight road, it travels in a single direction without deviating from its path. The road itself provides a straight and level surface, allowing the car to maintain a consistent direction of motion.

As the car moves forward, it travels along the straight road, covering distances in a linear manner. The car's position changes linearly with time as it progresses along the road. In rectilinear motion, the object's direction of motion remains constant throughout the motion.

Since the car moves along a straight road without turning or changing its path, its direction remains unchanged. The situation of a car moving on a straight road perfectly fits the definition of rectilinear motion. The motion of the car is characterized by its movement along a straight path without any change in direction.

In summary, a car moving on a straight road is an example of rectilinear motion because it travels along a straight path without changing its direction. This motion is linear and occurs in a single dimension, making it a clear illustration of rectilinear motion.