STANDARD FORM
TIP: When doing these sort of problems, remember:
a) Standard form is simply a way of writing very large and very small numbers without having to write loads of numbers.
b) Here is a number in standard form:
6.3 x 108
Note:
The
part before the multiplication sign (6.3 in
our example) can only have one digit (number) before the decimal point.
The part after the multiplication sign (108
in our example) is always 10 to the power a number.
c) To convert decimal numbers less than 1 to standard form:
e.g 0.0082 = 8.2/1000 = 8.2 x 1/1000 = 8.2 x 1/103 = 8.2 x 10-3
Do the same in reverse to convert a standard form number back to a decimal one.
d) When converting numbers greater than one, use the same technique but multiply, instead of divide.
e) When doing calculations using numbers in standard form, remember the indices rules practice them here.
Solve the following:
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1. Write 0.000008 in standard form. |
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2. Write 453000000 in standard form |
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3. Change 5.2 x
108 to an ordinary |
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4. Change 1.65 x 10-5 to an ordinary decimal number. |
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5. What is |
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6. The diameter of the Earth is; The diameter of Mars is: What's the difference between the two diameters?
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7. The mass of an electron is: How could this mass be written in standard form? What is the mass of 8,000,000 electrons?
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8. The distance between the Earth and the star Sirius is: If light travels 3 x 105 km per second, how many seconds does it take for light to travel from Sirius to the Earth? (give your answer to 2 significant figures)
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