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Motion in 1 Dimension — JEE Main Physics MCQs with Solutions
Free JEE Main Physics Motion in 1 Dimension MCQs with step-by-step solutions covering Distance, Displacement, Speed, Velocity, Acceleration, Motion Under Gravity. Practise online on Prepizo — no login needed.
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Sample questions with solutions
Q1 — Distance · easy · theory
Distance is a
A. Dimensionless quantity
B. Scalar quantity ✓ Correct
C. Unit vector
D. Vector quantity
Solution: Distance (path length) has magnitude only — it is a scalar.
Q2 — Distance · easy · theory
A particle completes one full lap of a circular track of radius $r$. The distance travelled is
A. $2r$
B. $\pi r$
C. $2\pi r$ ✓ Correct
D. Zero
Solution: The path length of one full circle is its circumference, $2\pi r$.
Q3 — Distance · easy · theory
A particle covers half a lap of a circular track of radius $7$ m. The distance travelled is (take $\pi = \frac{22}{7}$)
A. $14$ m
B. $22$ m ✓ Correct
C. $7$ m
D. $44$ m
Solution: Half the circumference $= \pi r = \frac{22}{7}\times 7 = 22$ m.
Q4 — Distance · easy · theory
The odometer of a car measures
A. Average velocity
B. Displacement
C. Distance travelled ✓ Correct
D. Instantaneous velocity
Solution: The odometer adds up the path length — total distance, regardless of direction.
Q5 — Distance · easy · theory
A person walks $3$ m east and then $4$ m north. The total distance covered is
A. $12$ m
B. $5$ m
C. $1$ m
D. $7$ m ✓ Correct
Solution: Distance adds the path lengths: $3 + 4 = 7$ m. (The displacement would be $5$ m.)
Q6 — Distance · easy · theory
The distance travelled by a particle can be
A. Never negative ✓ Correct
B. Less than the magnitude of its displacement
C. Zero while the particle keeps moving
D. Negative
Solution: Path length only accumulates — it can never decrease or be negative.
Q7 — Distance · easy · numerical
A car goes $40$ km forward and then $20$ km back towards the start. The total distance travelled is
A. $20$ km
B. $40$ km
C. $60$ km ✓ Correct
D. $30$ km
Solution: Distance $= 40 + 20 = 60$ km (the displacement would be $20$ km).
Q8 — Distance · easy · theory
A particle moves along the x-axis from $x = 2$ m to $x = 7$ m, then back to $x = 3$ m. The total distance travelled is
A. $4$ m
B. $1$ m
C. $5$ m
D. $9$ m ✓ Correct
Solution: Forward $5$ m, then back $4$ m: distance $= 5 + 4 = 9$ m.
Q9 — Distance · easy · theory
A body moves with uniform speed $v$ for time $t$. The distance covered is
A. $vt^2$
B. $vt$ ✓ Correct
C. $\frac{v}{t}$
D. $\frac{1}{2}vt$
Solution: For uniform speed, distance $=$ speed $\times$ time $= vt$.
Q10 — Distance · easy · theory
A ball is dropped from $20$ m, bounces, and is caught when it reaches $5$ m height. The total distance travelled is
A. $5$ m
B. $25$ m ✓ Correct
C. $20$ m
D. $15$ m
Solution: Down $20$ m plus up $5$ m: total path $= 25$ m.
Q11 — Distance · easy · theory
The area under a speed–time graph gives
A. Acceleration
B. Distance travelled ✓ Correct
C. Displacement (with sign)
D. Average speed
Solution: Speed is never negative, so the area under speed–time accumulates the total path length.
Q12 — Distance · easy · numerical
A man walks $8$ km north and then $6$ km south. The distance travelled is
A. $10$ km
B. $8$ km
C. $14$ km ✓ Correct
D. $2$ km
Solution: Path length adds: $8 + 6 = 14$ km. (Displacement is only $2$ km north.)
Q13 — Distance · easy · theory
As time passes, the distance travelled by a moving particle
A. Can never decrease ✓ Correct
B. Can decrease if it turns back
C. Can become zero again
D. Oscillates for oscillatory motion
Solution: Path length keeps accumulating — turning back adds more distance, never removes it.
Q14 — Distance · easy · theory
The SI unit of distance is
A. metre ✓ Correct
B. centimetre
C. kilometre
D. mile
Solution: The SI base unit of length is the metre (m).
Q15 — Distance · easy · numerical
An athlete completes $5$ laps of a $400$ m track. The distance covered is
A. Zero
B. $400$ m
C. $2$ km ✓ Correct
D. $4$ km
Solution: $5 \times 400 = 2000$ m $= 2$ km. (Displacement per complete lap is zero.)
Q16 — Distance · easy · theory
A particle moves at a constant speed of $5$ m/s for $10$ s. The distance covered is
A. $2$ m
B. $50$ m ✓ Correct
C. $15$ m
D. $5$ m
Solution: Distance $= 5 \times 10 = 50$ m.
Q17 — Distance · easy · numerical
A person walks $3$ km north, $4$ km east and then $3$ km south. The total distance is
A. $6$ km
B. $10$ km ✓ Correct
C. $4$ km
D. $5$ km
Solution: Distance adds all legs: $3+4+3 = 10$ km. (Displacement is $4$ km east.)
Q18 — Distance · easy · theory
A light year is a unit of
A. Time
B. Speed
C. Intensity of light
D. Distance ✓ Correct
Solution: A light year is the distance light travels in one year ($\approx 9.46\times10^{15}$ m).
Q19 — Distance · easy · numerical
Two towns are $60$ km apart. A bus goes from one to the other and returns. The distance covered is
A. Zero
B. $30$ km
C. $120$ km ✓ Correct
D. $60$ km
Solution: Round trip: $60 + 60 = 120$ km, while displacement is zero.
Q20 — Distance · easy · theory
A particle moves as $x = t^2$ (metres, seconds) from $t=0$ to $t=3$ s. The distance travelled is
A. $9$ m ✓ Correct
B. $27$ m
C. $6$ m
D. $3$ m
Solution: $v = 2t \geq 0$ throughout (no reversal), so distance $= x(3) - x(0) = 9$ m.
Q21 — Distance · easy · theory
The dimensional formula of distance is
A. $[ML]$
B. $[LT^{-1}]$
C. $[L]$ ✓ Correct
D. $[LT^{-2}]$
Solution: Distance is a length: dimension $[L]$.
Q22 — Displacement · easy · theory
Displacement is a
A. Dimensionless quantity
B. Scalar quantity
C. Always positive quantity
D. Vector quantity ✓ Correct
Solution: Displacement has both magnitude and direction — the vector from initial to final position.
Q23 — Displacement · easy · theory
A particle moves along half a circle of radius $r$. The magnitude of its displacement is
A. $\pi r$
B. $r$
C. Zero
D. $2r$ ✓ Correct
Solution: Start and end are at opposite ends of a diameter: displacement $= 2r$.
Q24 — Displacement · easy · theory
In one-dimensional motion, displacement
A. Can never be zero
B. Is always equal to distance
C. Is always positive
D. Can be positive, negative or zero ✓ Correct
Solution: The sign shows direction along the chosen axis; returning to start makes it zero.
Q25 — Displacement · easy · theory
A body completes a round trip and returns to its start. Its displacement is
A. Twice the one-way distance
B. Zero ✓ Correct
C. Negative
D. Equal to the total path
Solution: Same start and end point $\Rightarrow$ zero displacement.
Q26 — Displacement · easy · theory
A particle moves from $x = +5$ m to $x = -3$ m. Its displacement is
A. $-2$ m
B. $+8$ m
C. $+2$ m
D. $-8$ m ✓ Correct
Solution: $\Delta x = x_f - x_i = -3 - 5 = -8$ m (8 m in the negative direction).
Q27 — Displacement · easy · theory
The displacement between two given points
A. Equals the longest path
B. Is undefined for curved paths
C. Depends on the path
D. Is the same for every path taken ✓ Correct
Solution: Displacement depends only on the endpoints, not on the route between them.
Q28 — Displacement · easy · theory
A man walks $8$ km north and then $6$ km south. His displacement is
A. $14$ km
B. $10$ km
C. $2$ km south
D. $2$ km north ✓ Correct
Solution: Net position change: $8 - 6 = 2$ km towards the north.
Q29 — Displacement · easy · theory
The SI unit of displacement is
A. kilometre
B. metre ✓ Correct
C. newton
D. metre/second
Solution: Displacement is a length — measured in metres, with a direction attached.
Q30 — Displacement · easy · theory
After every complete lap on any closed track, the displacement of a runner is
A. The track length
B. The track diameter
C. Zero ✓ Correct
D. Doubles each lap
Solution: Each complete lap returns the runner to the same point, resetting displacement to zero.