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Lesson 12 of 16

The smallest tick

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5 min

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Two sprinters, A and B, finish a short race. A wall clock reads 12 s for both. Who won?

A wall clock ticks once a second. A tick is its smallest time step. Both read 12 s. A tie.
Step 1 of 3
  1. A wall clock ticks once a second. A tick is its smallest time step. Both read 12 s. A tie.
  2. A watch ticks every 0.1 s. Both read 12.4 s. Still a tie.
  3. A sports timer ticks every 0.01 s. Now A wins.

A ran 12.46 s and B ran 12.49 s. A took less time, so A won. A clock needs 0.01 s , or smaller, to show this.

The new word

  • Tick — the smallest gap of time a clock can show.

The rule

A clock cannot show a gap smaller than its smallest . To tell close times apart, use a smaller tick.

Sprint races are timed to hundredths of a second, or even thousandths. A hundredth of a second is 0.01 s.

Now try it. Slide to a smaller . Can the clock tell the sprinters apart?

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