To express the number 0.0000785 in scientific notation, we need to rewrite it in the form of A × 10B, where A is a number greater than or equal to 1 and less than 10, and B is an integer.
First, we identify where to place the decimal point to create a number between 1 and 10. For 0.0000785, we move the decimal point 4 places to the right to get 7.85.
Since we moved the decimal to the right, this indicates a negative exponent. Therefore, we write:
7.85 × 10-5
This means that 0.0000785 can be expressed as 7.85 × 10-5 in scientific notation.