- #1

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## Homework Statement

A turtle and a rabbit engage in a footrace over a distance of 4.00km. The rabbit runs 0.500km and then stops for a 90min nap. Upon awakening, he remembers the race and runs twice as fast. Finishing the course in a total time of 1.75h, the rabbit wins the race.

A) Calculate the average speed of the Rabbit.

B) What was his average speed before he stopped for a nap? Assume no detours or doubling back.

**The question is asking to find the answers in km/h**## Homework Equations

**Conversion****Average Velocity: Δd/Δt= df-di/tf-ti****T=D/T ; D=V⋅T**

## The Attempt at a Solution

1. I first labeled values.

[/B]

__Trip1__

**Δd:**0.500km

**AvgV:**?

**T:**? = 0.25h

__Break__

**T:**90.0min= 1.5h

**Trip2**

**2v1:**?= 4.58km/h

__Trip Total__

**Δd:**4.00km

**T:**1.75h

**AvgV:**2.29km/h

**2. I then solved for the average speed of the Rabbit**:

**Average Velocity: Δd/Δt= 4.00km/1.75h = 2.29km/h**

I'm guessing that if the rabbit was

__running twice the avg speed in trip 2__, I would have to multiply

**2.29km/h by 2**for the velocity of trip two.

**3. Next, I converted the Rabbits break time:**

4. Since the next step is asking for

~So I subtracted the rabbits total time by the break time and got:

__90.0mins to hours__and got__1.5 hours__4. Since the next step is asking for

__the average speed BEFORE the rabbit stopped to take a nap__, it requires more steps.~

**ΔT=0.25h**, or

**15 minutes.**The rabbit ran 15 minutes before taking a break.

~I then subtracted the distances of the total and trip 1 and

**Δd= 3.50km**

*This is where I got stuck. I'm not sure what to do next. I know that I'm supposed to calculate the average speed, so

**would that mean that I'm supposed to subtract the distances, divide by 0.25h, then subtract that average speed from the doubled speed of trip 2?**

**In that case, my answer was 9.5km/hr. But the book states that the answer is 9.0km/hr. What did I do wrong here?**