Question

question 8
the top speed of a pontiac gto 6.0 is 170.26 mph. given that 1 km = 0.62137 mi and 1 hr = 60 min = 60 s, how fast is this in km/s?
express your answer using the correct number of significant digits.

• 1.01 x 10⁻⁶ km/s
• 0.076113 km/s
• 1.0117 x 10⁻⁶ km/s
• 0.0761131 km/s

Explanation:

Step1: Convert miles to kilometers

$\text{Speed in km/hr} = 170.26 \, \text{mi/hr} \times \frac{1 \, \text{km}}{0.62137 \, \text{mi}} \approx 274.01 \, \text{km/hr}$

Step2: Convert hours to seconds

$\text{Speed in km/s} = 274.01 \, \text{km/hr} \times \frac{1 \, \text{hr}}{3600 \, \text{s}} \approx 0.076113 \, \text{km/s}$

Step3: Confirm significant digits

The original value 170.26 has 5 significant digits, and the conversion factors are exact, so the result retains 5 significant digits.

Answer:

0.076113 km/s