In helical gears, the right hand helices on one gear will mesh ____________ helices on the other gear.
(a) right hand
(b) left hand
(c) opposite
(d) none of the mentioned
The question was asked by my school teacher while I was bunking the class.
Enquiry is from Standard Proportions of Gear Systems topic in chapter Toothed Gearing & Gear Trains of Machine Kinematics