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ArbitrLikvidat [17]
3 years ago
14

Simon is riding a bike at 12 km/h away from his friend Keesha. He throws a ball at 5 km/h back to Keesha, who is standing still

on a sidewalk. How fast would Keesha say the ball is traveling?
Physics
1 answer:
pychu [463]3 years ago
3 0
So there are different ways this could be solved. I'll do try to explain it the way I was taught... 

Simon is riding his bike at 12 km/hr relative to the sidewalk, away from where Keesha is.

Simon throws the ball at Keesha, at 5 km/hr. 

Keesha sees the ball approaching her at (12-5) = 7 km/hr relative to the ground to her. 

Therefore the answer is: 7 km/hr


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The total amount of heat needed will be Q_T=21.411kcal.

Explanation:

We will divide the calculation in two: First, the heat needed to melt the ice, and then the heat needed to warm the resulting liquid from 0°C to 37°C.

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A man pushing a mop across a floor causes it to undergo two displacements. The first has a magnitude of 152 om and makes an angl
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Answer:

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\beta = tan^{-1} \frac{62.18}{155.22 }

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