How many 360° rotations will a bicycle wheel, with a diameter 0.5 mete

Question

How many 360° rotations will a bicycle wheel, with a diameter 0.5 meters including the tyre, will make while travelling a distance of 100 meters?

(A) 50π 
(B) 50/π 
(C) 100π
(D) 100/π 
(E) 200/π

RicAssassin · Answer

Answer is D.

The wheel will cover pi*d meters in a single whole rotation.

For 100m. 100/(pi*1)

Hence D

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KS15 · Answer

It should be E i.e 100/0.5pie=200/pie

RicAssassin · Answer

My bad. I read the DIAMETER as radius. I was just out if a meeting. SILLY FRIGGIN MISTAKE!!

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JeffTargetTestPrep · Answer

Since the diameter is 0.5 meters, the circumference is 0.5π meters and, thus, in 100 meters, the bike will make 100/(0.5π) = 200/π rotations.

Answer: E

generis · Answer

Circumference of wheel =   \frac{1}{2}\pi m

Distance, d = 
(# of revolutions, R) * (circumference, c, of wheel)

R revolutions =  \frac{D}{c}

R = \frac{100m}{\frac{1}{2}\pi m} = \frac{200}{\pi}

Answer E

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