Physics · Motion In A Straight Line · NEET
No. A negative position only tells you the object is on the negative side of the origin, not which way it is moving. Direction of motion is shown by the sign of velocity, not by the sign of position. An object at x = -5 m can still be moving in the positive direction (velocity positive), which means its position value is increasing toward 0 and then to positive values.
The origin is the point you decide to call x = 0. All positions are measured from it. You need it because position has no meaning until you fix a reference point. Choosing a convenient origin (like the starting point of the object) makes the numbers simple. The physics answer does not change if you shift the origin, but the numbers for x will change.
You choose it yourself at the start of the problem, then keep it the same for the whole problem. A common choice is: to the right or upward is positive, to the left or downward is negative. Once fixed, velocity, acceleration, and g must all follow the same rule. Changing the positive direction midway is a common mistake that flips signs and gives wrong answers.
No. Position is a single value with a sign that tells location relative to the origin. Distance is the total path length actually covered and is always positive. Two objects at x = +4 m and x = -4 m are at different positions but both are 4 m away from the origin. This distance-vs-position idea leads into distance vs displacement.
Yes. If an object starts at x = +5 m, moves away, and returns to x = 0 (the origin), its position is now 0 even though it travelled a real path. Position 0 just means the object is exactly at the origin at that instant. This is why position and distance travelled are different quantities.
A particle moves along a straight line with position s(t) = alpha*t^2 - beta*t + gamma, where alpha = 1 m/s^2, beta = 6 m/s, gamma = 5 m. The average speed of the particle (in m/s) from t = 0 to t = 6 s is:
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Position x is the location of an object measured along a straight line from a fixed reference point called the origin. It carries a sign: positive on one chosen side of the origin and negative on the other. Position tells you where the object is, not how far it has travelled.
The sign tells you which side of the origin the object is on. Positive x means the object is on the side you chose as the positive direction; negative x means the opposite side. The sign does not tell you the direction of motion, only the direction of location from the origin.
Position, displacement, and the sign convention for velocity, acceleration, and g all depend on the origin and positive direction you pick. Fixing them at the start and keeping them consistent prevents sign errors, which are among the most common mistakes NEET students make in motion and free-fall problems.
In one dimension, position is treated as a scalar with a plus or minus sign that stands in for direction along the line. In full form it is a vector quantity, but along a straight line the sign (+ or -) fully captures its direction, so a signed number is enough.
Yes. An object at x = +6 m and another at x = -6 m are both 6 m from the origin, so their distances from the origin are equal, but their positions are different because they are on opposite sides. This shows why position and distance are not the same thing.
