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Physics · Units & Dimensions

Units & Dimensions

Tap a card to begin — drag with your finger, build formulas, and watch the ideas move.

01

Fundamental vs Derived

Drag each quantity into the right bucket. Instant feedback, live score.

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02

Scalar vs Vector

Sort quantities by whether direction matters. Catch the tricky ones.

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03

SI Prefix Reference

All 15 prefixes with their powers and real-world anchors — ready to put on the board.

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04

Unit Converter

Type any value — instantly see it in every unit. Length, mass, and time.

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05

The cm² Surprise

How many cm² in 1 m²? Let them guess, then reveal the 10,000-square truth.

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06

Dimension Builder

Dial in the M, L, T powers to build a quantity's dimensional formula.

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07

Dimensional Formulas

Every quantity from mechanics to G, h, and η — revealed one at a time.

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08

Same Dimensions

Work and Torque both [ML²T⁻²]? Reveal each group and see which quantities share a formula.

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09

Equation Checker

Tap each equation to check it term by term. Can you catch the wrong ones?

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10

Formula Forge

Turn the power-dials, balance M·L·T, and derive a physics law from dimensions alone — no experiment needed.

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11

Error Bar Explorer

Stretch the measurement and its error — watch the percentage error react live.

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12

Master Dimension Sheet

Every dimensional formula on one screen — from M, L, T up to G and h. Display it, then have the class copy it out.

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13

Revision

Seven mixed JEE-level problems, one per concept from Lectures 1–6. Tap to reveal each solution.

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14

Significant Figures

The 6 counting rules, revealed one at a time with worked examples.

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15

The Add vs Multiply Trap

The most common careless mistake in the chapter — tap an answer and see why.

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16

Types of Error

Real scenarios — classify each as Systematic, Random or Gross, then check yourself.

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17

Vernier Calipers (Interactive)

Drag the jaw to measure real objects, switch the least count, add zero error, and read the vernier with a live magnifier — plus a quiz mode.

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18

Lecture 12 — Vernier & Screw Gauge PYQs

The real JEE Main PYQs and drill questions from Lecture 12, revealed one at a time. Question only — solve it before moving to the next.

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Lecture 12 — Vernier & Screw Gauge PYQs
Reveal one question at a time. Solve it on the board before moving on.
1/8
Question
Vernier Calipers — Interactive Lab
Drag the jaw · read the scales · master least count & zero error.
Fundamental vs Derived
Drag a card into a bucket — or tap a card, then tap a bucket.
0
Placed

Fundamental

The 7 independent base quantities

Derived

Built from the fundamentals
🎉 All sorted correctly! Well done.
Scalar vs Vector
Drag a card — or tap a card, then tap a bucket. Does direction matter?
0
Placed

Scalar

Magnitude only — no direction

Vector

Magnitude + direction
🎉 Every one correct! Direction mastered.
Dimension Builder
Set the powers of M, L and T to match the quantity.
0
Solved
Build the dimensional formula of
Speed
Your formula
[ M⁰ L⁰ T⁰ ]
MMass 0
LLength 0
TTime 0
The cm² Surprise
A 1-metre square. How many 1-cm squares fit inside?
1 m = 100 cm
1 m = 100 cm

How many cm²
in 1 m²?

Let the class commit to an answer first — then tap it to reveal.

0
cm² squares filling 1 m²
Error Bar Explorer
Same absolute error feels very different at different sizes.
Measurement
50 ± 1.0
Relative error
0.020
Percentage error
2.0%
Unit Converter
Tap any result card to make it the input unit — instantly see all conversions.
Dimensional Formulas
Tap any card to see the full step-by-step derivation.
Basic — from Lecture 2 homework
Core Mechanics
Tricky — JEE favourites
Dimensional Formula
Same Dimensions
Same formula ≠ same quantity. Reveal each group and discuss what makes them different.
0 / 5
Equation Checker
Tap any equation to check it term by term. Cards stay green, red, or amber after you reveal them.
Lecture Examples
Practice Problems
HW Equations
Revision
Seven mixed problems — one per concept from Lectures 1–6. Decide the technique, then reveal the solution.
1 / 7
Problem
Significant Figures
The 6 counting rules, revealed one at a time with worked examples.
0 / 6
The Add vs Multiply Trap
The most common careless mistake in the chapter — tap an answer and see why.
Types of Error
Real scenarios — classify each as Systematic, Random or Gross, then check yourself.
Formula Forge
Derive a physics formula from dimensions alone — the power-law method made tangible.

Every quantity below depends on a few ingredients. Set the power of each ingredient so the total dimensions of M, L and T match the target. When all three lock in, the formula crystallizes — exactly how physicists guess the form of a law before ever running an experiment.

Forge the formula for
It depends on these — dial in each power
⚒ Balance M, L and T to forge the formula
Master Dimension Sheet
Every dimensional formula on one page — fundamentals first, then everything built from them.

📋 Display this on the board and have the class copy the full table onto one sheet of paper.

SI Prefix Reference
Prefixes are multipliers attached to a unit to express very large or very small quantities without writing long strings of zeros — all 15, with a real-world anchor for each.
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Large — positive powers
Small — negative powers
Special Unit — not a prefix, but used everywhere
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