Answer:
12 minutes
Option D
Step-by-step explanation:
Given that circuar gears P and Q start rotating at the same time at constant speeds.
Gear P makes 10 revolutions per minute and Gear Q makes 40 revolutions per minute.
Both gears start at the same time.
No of rotations per minute are 10 and 40
Difference is 30 in one minute
For 6 difference we must have exactly 1/5 minutes
which equals 12 seconds.
In 1/5 minutes or 12 seconds gear P would have completed 2 revolutions while Gear Q would have completed 8 revolutions thus making difference as 6.
