Question

Which of the following speeds is maximum?

• A. \(7.3 \frac{m}{s}\)
• B. \(28.4 \frac{km}{h}\)
• C. \(6.5 \frac{m}{min}\)
• D. \(0.0073 \frac{km}{s}\)

Answer 1

The Correct Option is B

To determine which speed is the maximum, we must convert all given speeds to the same unit for comparison. We will convert each speed to meters per second (m/s), taking note of each step.

• \(7.3 \frac{m}{s}\): This speed is already in meters per second.
• \(28.4 \frac{km}{h}\): To convert from kilometers per hour to meters per second, use the formula: \(1 \frac{km}{h} = \frac{1000}{3600} \frac{m}{s}\) or approximately \(0.2778 \frac{m}{s}\). Therefore, \(28.4 \frac{km}{h} \times 0.2778 \approx 7.89 \frac{m}{s}\).
• \(6.5 \frac{m}{min}\): To convert from meters per minute to meters per second, divide by 60: \(6.5 \div 60 \approx 0.1083 \frac{m}{s}\).
• \(0.0073 \frac{km}{s}\): To convert from kilometers per second to meters per second, multiply by 1000: \(0.0073 \times 1000 = 7.3 \frac{m}{s}\).

Now, compare the converted speeds:

Original Speed	Converted Speed (m/s)
\(7.3 \frac{m}{s}\)	7.3
\(28.4 \frac{km}{h}\)	7.89
\(6.5 \frac{m}{min}\)	0.1083
\(0.0073 \frac{km}{s}\)	7.3

The maximum speed is \(28.4 \frac{km}{h}\) when converted as shown, with a result of \(7.89 \frac{m}{s}\).