Question

It has been proposed that North America is moving west at about 2 cm per year. How many kilometers would it move in 5,000 years? (Note: 2 cm is a measurement so your final answer should have significant figure rules applied.)

a) 10 km
b) 100 km
c) 1 km
d) 0.1 km

Answer 1

North America would move a total of 0.1 km in 5,000 years at a rate of 2 cm per year, as we calculate the distance by multiplying the annual movement rate by the number of years and converting the result to kilometers, while applying significant figure rules.

Step-by-step explanation:

To calculate the distance North America would move in 5,000 years at a rate of 2 cm per year, we need to multiply the annual movement rate by the number of years:

Distance moved = Movement rate per year × Number of years

Distance moved = 2 cm/year × 5,000 years

Distance moved = 10,000 cm

Since there are 100,000 cm in a kilometer, we convert the distance traveled from centimeters to kilometers:

Distance moved in kilometers = Distance moved in centimeters ÷ 100,000 cm/km

Distance moved in kilometers = 10,000 cm ÷ 100,000 cm/km

Distance moved in kilometers = 0.1 km

Applying the significant figure rules from the measurement given (2 cm has one significant figure), the distance should also be represented with one significant figure.

Therefore, the correct answer is (d) 0.1 km.