Question

A bike has 2 wheels of different sizes. Front wheel is bigger. The smaller wheel rotates 5 times faster than the bigger wheel. The radius of the smaller wheel is 5 inches and the bike moves 3 feet per second. What ia the radius of the bigger wheel?


A little help here please. I'm a bit confused on what i am going to do with the '5 times' thingy, i mean, how am i going to epress it and etc :)

Answer 1

@kmed is your answer 1

Answer 2

@Abmon u mean, 1in?

Answer 3

yes

Answer 4

Yah. I used the formula for circumference. I did it like this:
(5)2rpi = 2rpi
(5)2rpi = 2(5in)pi
r = 1in

Answer 5

good job @kmeds16 :D

Answer 6

@Abmon98 thank you! :) so the final answer is really r = 1in right? :)

Answer 7

your welcome @kmeds16 i am not sure ask more people :)

Answer 8

@cwrw238 hii, a little help please? :)

Answer 9

@jim_thompson5910 help me please :)

Answer 10

What's your question? It looks answered already?

Answer 11

Looking for more answers & verifications :) most especially from the experts i know :)

Answer 12

I think my answer is incorrect.

Answer 13

I'm getting r = 1 as well

Answer 14

to be more specific, I'm getting 1 ft

not 1 inch

Answer 15

remember the smaller wheel has a radius of 5 inches

so the answer has to be larger than 5 inches

Answer 16

@jim_thompson5910 oh yes yes yes that's what im thinking, so that means it's in feet haha thank you :) so the radius of the bigger wheel is 12 inches coz 1ft is equal to 12 in right

Answer 17

actually I converted wrong, but I redid it. I'm getting this now


v = w1*r1
36 = w1*5
36/5 = w1
w1 = 36/5


w2 = (1/5)*w1

v = w2*r2
v = (1/5)*w1*r2
36 = (1/5)*36/5*r2
(r2)/25 = 1
r2 = 25


So the bigger wheel has a radius of 25 inches

Answer 18

@jim_thompson5910 ohh i see. Thank you so much! :)

Answer 19

np