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Bill is not only good at riding a bike with no hands, but he can also ride the bike with no hands and facing backwards while the bike goes forward. Bill is riding his bike in such a manner while playing catch with Betty who is stationary on the ground and facing Bill. Bill is on the bike (facing backwards toward Betty) and traveling away from Betty at a speed of 12.0 m/s when he throws a ball to Betty at a speed of 17.8 m/s relative to the bike. What is the velocity of the ball as measured by Betty

User Irving
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1 Answer

9 votes

Answer:

5.8 m/s

Step-by-step explanation:

Let v = velocity of bike relative to Betty = -12.0 m/s (since the bike is moving away from betty).

u = velocity of ball relative to bike = + 17.8 m/s

and V = velocity of ball relative to Betty.

So, by Galilean relativity,

V = v + u

V = -12.0 m/s + 17.8 m/s

V = 5.8 m/s

So, the velocity of the ball as measured by Betty is 5.8 m/s

User Jan Berndt
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