Sign in
Please select an account to continue using cracku.in
↓ →
Wheels of diameters 7 cm and 14 cm start rolling simultaneously from X and Y, which are 1980 cm apart, towards each other in opposit directions. Both of them make same number of revolutions per second. If both of them meet after 10 seconds, the speed of the smaller wheel is
Distance covered by big wheel in 1 revolution = $$2\pi r$$
= $$2\times\frac{22}{7}\times7=44$$ cm
and by small wheel = $$22$$ cm
Since, distance $$\propto$$ speed
Let speed of small wheel = $$x$$ cm/s, => Speed of big wheel = $$2x$$ cm/s
Also, relative speed of both wheels = $$\frac{1980}{10}=198$$ cm
=> $$x+2x=198$$
=> $$x=\frac{198}{3}=66$$ cm/s
=> Ans - (C)
Create a FREE account and get:
Book Free CAT Mentorship
Get personalized CAT strategy from a 99%iler
500+ students mentored
OTP Verification
Enter the 6-digit code sent to your phone
Booking Summary
Enter OTP
Didn't receive the OTP?
Educational materials for CAT preparation