Question

A scientist measured the wavelength of an X-ray as 0.0000000065 meters.

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​Write the number in scientific notation.

Answer 1

6.5 * 10^-9 metres.

Explanation:

This is < 1 so the exponent is negative

We count the number of digits after the decimal point up to and including the first digit > 0.

This is 9 digits.

So the answer is 6.5 * 10^-9.

Answer 2

6.5 * 10 ^ -9

Explanation:

0.0000000065

Scientific notation means a* 10 ^b

where a is number between 1 and less than 10

Move the decimal 9 places to the right which means the power of 10 is negative since we moved the decimal to the right

6.5

The power of 10 is -9

6.5 * 10 ^ -9