Distance & Time

• How distance (how far) and time (how long) describe motion in everyday life.
• To measure distance with standard tools — metre scale, trundle wheel — and time with clocks.
• The difference between uniform and non-uniform motion using distance–time descriptions.
• To read simple distance–time tables and describe a journey in words.

Level 1 — Measuring distance and time

Verbal: Distance is the length of the path travelled. Time is the interval during which motion occurs.

Symbolic: If you walk from home to school in 15 minutes covering 800 m, distance = 800 m, time = 15 min.

Visual (journey table):

Tools: Metre tape for room length; stopwatch for race time; wall clock for daily time (NCERT "Motion and Measurement").

Level 2 — Types of motion and graphs (tabular)

Uniform motion: Equal distances in equal intervals — steady pace on a straight track.

Non-uniform motion: Unequal distances in equal time — crowded bus, stopping at signals.

Straight line vs curved path: Distance along path may exceed straight-line separation (displacement is Class 7+; Class 6 focuses on path length).

Real world: Odometer in vehicles measures distance travelled; fitness bands measure steps and time.

A student walks 200 m to the library in 4 minutes, stays 6 minutes, then walks 200 m back in 4 minutes. Describe the trip.

Step 1 — Outward: distance 200 m, time 4 min (uniform if steady walking)
Step 2 — At library: distance unchanged, time +6 min (rest)
Step 3 — Return: 200 m in 4 min
Step 4 — Total distance = 200 + 200 = 400 m; total time = 4 + 6 + 4 = 14 min

• Define distance and time in your own words.
• A car travels 60 km in 1 hour, then 30 km in the next 2 hours. Is the motion uniform overall?
• Why do scientists prefer SI units when recording measurements?
• Sketch a table for a 100 m race with start, 50 m mark, and finish times.

Open the Practice tab for graded questions on Distance & Time.