Conversions & Standard Form Flashcards

All 6 cards in this deck

How do you convert a time in hours into seconds?

Multiply by 3600 ($60 \times 60$).
To go back from seconds to hours, divide by 3600.

How do you convert a speed in km/h into m/s?

Multiply by 1000 (km to m), then divide by 3600 (hours to seconds) — the same as dividing by 3.6.

What is standard form?

A number written as $A \times 10^n$, where $1 \le A < 10$.
e.g. $4500 = 4.5 \times 10^3$

True or false? $2.5 \times 10^{-3}$ written as an ordinary number is 0.0025.

True. A negative power of 10 moves the digits that many places to the right.

When counting significant figures, which digit do you start from?

The first non-zero digit. e.g. in 0.04863 the first significant figure is the 4.

If every measurement in a question is given to 2 significant figures, to how many significant figures should you give your calculated answer?

2 significant figures — match the number of significant figures in the data given.