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3 years ago

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John is preparing for his way to school. His house is 30 km away. What time will he be in school if he leaves his house at 6:30

AM and travels at an average speed of 40 km/hr?

1 answer:

Goshia [24]3 years ago

7 0

Answer:

Jio will be at school at 7:15 a.m.

Explanation:

Formula:

t= s/v =(30km)/(40km/h) =0.75•60min=45min.

Then, Jio will be at school at 6:30a.m. + 45min =7:15a.m.

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a particle is moving along a circular path having a radius of 4 in such that its position as a function of time is given by thet

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Answer:

Explanation:

Given

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3 years ago

A key falls from a bridge that is 45 m above the water. the key falls straight down and lands in a model boat traveling at a con

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Let the key is free falling, therefore from equation of motion

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3 years ago

You set your stationary bike on a high 80-N friction-like resistive force and cycle for 30 min at a speed of 8.0 m/s . Your body

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A) The change in internal chemical energy is $1.15\cdot 10^7 J$

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First of all, we start by calculating the power output of you and the bike, given by:

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The energy output is related to the power by the equation

$P=\frac{E}{t}$

where:

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$E=Pt=(640)(1800)=1.15\cdot 10^6 J$

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B)

From the previous part, we found that in a time of

t = 30 min

the amount of internal chemical energy converted is

$E=1.15\cdot 10^7 J$

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So we can setup the following proportion:

$\frac{t}{E}=\frac{t'}{E'}$

And solving for t',

$t'=\frac{E't}{E}=\frac{(3.8\cdot 10^5)(30)}{1.15\cdot 10^7}=1 min$

Learn more about power and energy:

brainly.com/question/7956557

#LearnwithBrainly

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