Physics · Motion In A Straight Line · NEET
Yes, they mean exactly the same thing. NCERT itself says: motion of an object along a straight line is 'also known as rectilinear motion.' 'Recti-' comes from the Latin word for straight. So whenever a question says rectilinear motion, picture the object moving on one straight path, back and forth if needed, but never turning off that line.
No. Rectilinear only tells you about the path (a straight line), not about the speed. In rectilinear motion the object can speed up, slow down, stop, or even reverse — it just cannot leave the straight line. A car braking on a straight road, or a ball thrown up and falling back, are both rectilinear even though the speed keeps changing.
For NEET purposes, yes — they are treated as the same. Because the path is a straight line, you only need ONE axis (say the x-axis) to describe the whole motion. That is why it is called one-dimensional motion. Position is given by a single number x, with a plus or minus sign showing direction. This is why the chapter is the easiest starting point in Kinematics.
Yes. A freely falling ball moves straight down along a vertical line, so it is rectilinear motion (also called free fall). A ball thrown straight up and coming back down is also rectilinear, because up and down are along the same straight line — we just use plus for up and minus for down (or the reverse).
Because it is the simplest kind of motion. With a straight-line path you need only one axis, so the three equations of motion (v = u + at, s = ut + ½at², v² = u² + 2as) apply directly with signs. Once you master signs and these equations here, projectile and 2D motion in the next chapter become much easier.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
It is the motion of an object along a single straight line. The object may speed up, slow down or reverse, but it always stays on that one straight path. Example: a train moving on a straight track.
A car moving on a straight road and a ball falling straight down from a height. Both move along a straight line, so both are rectilinear motion.
Rectilinear motion is a type of motion, not a quantity, so it is neither. But because the path is a straight line, the vector quantities in it (like displacement and velocity) point along that one line, so we can handle their direction using just a plus or minus sign.
In rectilinear motion the path is a straight line, so direction stays along one axis. In circular motion the path is a curve (a circle), so the direction of motion keeps changing at every point. NEET Chapter 2 deals only with rectilinear motion.
Because a straight-line path needs only one coordinate axis to describe it. A single number x (with a + or − sign) fully gives the object's position, so it is one-dimensional.
