The speedometer of a car shows 36 km/hr. The angular speed of the wheels having 0.5m radius is:
Correct answer: D. 20 rad/sec
- A. 5 rad/sec
- B. 10 rad/sec
- C. 15 rad/sec
- D. 20 rad/sec
Explanation
To solve for the angular speed of the wheels, we first need to convert the car's speed from kilometers per hour to meters per second. The car's speed is given as 36 km/hr, which can be converted to m/s by multiplying by a factor of (1000 m / 1 km) * (1 hr / 3600 s) = 10 m/s. Next, we apply the relationship between linear speed (v) and angular speed (ω) using the formula: ω = v / r, where r is the radius of the wheel. Given that the radius (r) is 0.5 m, we substitute the values into the formula: ω = 10 m/s / 0.5 m = 20 rad/sec. Thus, the correct answer is 20 rad/sec. The other options are incorrect because they do not accurately reflect the conversion and calculation based on the given data.
This question appeared on the KMU MDCAT 2023 paper, which you can sit online with every answer explained.
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