A gear train is constructed with only two...

Question 1 of 270705eccef9dbacbc34ba4d45e02

A gear train is constructed with only two gears: a 2-inch (50.5 mm) diameter driving gear and a driven bull gear to rotate a propeller at 200 rpm. If the speed of the driving gear is 4,800 rpm, what is the diameter of the driven gear?

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Question 1 of 27070

🔍 Key Concepts

• Gear ratio relationship between driving gear speed and driven gear speed • How gear diameter (or number of teeth) relates to rotational speed in a simple two-gear train • Unit consistency when comparing inches and millimeters (though you only need one system to solve)

💭 Think About

• First, figure out how many times faster the driving gear is turning compared to the driven gear. What ratio do you get from 4,800 rpm and 200 rpm? • In a simple gear pair, how is the speed ratio related to the size (diameter or teeth) ratio of the two gears? Does the larger gear turn faster or slower? • Once you know the needed diameter ratio, what must the driven gear diameter be if the driving gear is 2 inches in diameter?

✅ Before You Answer

• Make sure you compute the speed ratio = driving speed ÷ driven speed correctly. • Check that your final driven gear diameter is larger than the driving gear, since it must reduce speed from 4,800 rpm down to 200 rpm. • Verify that your chosen answer’s diameter, when compared to 2 inches, gives a ratio that matches (or is extremely close to) the speed ratio you found.