Measurements Study Guide

Scientists created the International System of Units because:

• It standardizes measurements globally.

• It simplifies scientific calculations.

• It was mandated by the United Nations.

• It is based on ancient measurement systems.

What is the standard unit of mass in the SI system?

• Gram

• Kilogram

• Milligram

• Ton

How can you convert from one SI unit to another?

• By using conversion factors

• By guessing the value

• By using a calculator

• By measuring again

Use a ratio to convert 17.5 g to kg.

• 0.0175 kg

• 1.75 kg

• 0.175 kg

• 175 kg

Rewrite the number deleting all extra zeros to the right or to the left of the decimal point.

• 1.496

• 2.8

Write a multiplication symbol and the number 10 with an exponent. The exponent should equal the number of places that you moved the decimal point in step 2. If you moved the decimal point to the left, the exponent is positive. If you moved the decimal point to the right, the exponent is negative.

• 1.496 \times 10^8

• 2.8 \times 10^{-8}

Why is scientific notation a useful tool for scientists?

• It allows for easier comparison of very large or very small numbers.

• It makes calculations more complex.

• It is only used in theoretical physics.

• It is a way to avoid using decimals.

Calculate the percent error if the experimental value of the density of gold is 18.7 g/cm³ and the accepted value is 19.3 g/cm³.

• 2.6%

• 3.1%

• 3.6%

• 4.1%

Which of the following is NOT a unit in the SI system of units?

• kilogram
• second
• inch
• meter

What is the SI unit for mass?

• Kg

• m

• m/s

• N