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3 years ago

11

Julian and Joshua each maintain a constant speed as they run laps around a 400-meter track. In the time it takes Julian to compl

ete two laps, Joshua completes three laps. Julian runs each mile in 12 minutes. How many minutes does it take Joshua to run exactly one mile?

2 answers:

crimeas [40]3 years ago

8 0

Answer:

8

Explanation:

Marysya12 [62]3 years ago

5 0

Answer:

the time Joshua travels 1 mile is 12.5 min

Explanation:

Let's start by finding the distance traveled on each lap,

Let's reduce everything to the SI system

R = 400 m

d = 1 mile (1609 m / 1 mile) = 1609 m

L = 2 pi R

L = 2 pi 400

L = 2513 m

Let us form a rule of proportions if 2 turns of Julian is 3 turns Joshua, for 1 turn of Joshua how many turns Julian took

lap Julian = 2/3 turn Joshua

Let's calculate what distance is the same for both of them since they are on the same track

1 lap = 2513 m

d. Julian = 2/3 2513 m

d Julian = 1675 m distance Joshua

Let us form the last rule of three or proportions if 1609 m you travel in 12 min how long it takes to travel 1675 m

t Julian = 1675/1609 12

t = 12.5 s

Since this is the distance Joshua travels, this is the time Joshua travels 1 mile

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puteri [66]

Answer:

14.8 kg

Explanation:

We are given that

$m_1=43.7 kg$

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According to question

$T_2-m_2 g=m_2 a$

$T_2=m_2a+m_2g=m_2(a+g)=12.1(9.8+4.9)=177.87 N$

$T_1=m_1(g-a)=43.7(9.8-4.9)=214.13 N$

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$(T_2-T_1)r=I(-\alpha)=\frac{1}{2}Mr^2(\frac{-a}{r})=\frac{1}{2}Mr(-4.9)$

Where $\alpha=\frac{a}{r}$

$(177.87-214.13)=-\frac{1}{2}(4.9)M$

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5) A parallel series electric blasting circuit consists of 6 branches of 8 caps each. Cap legwire length is 28 ft. The cap circu

andrezito [222]

Answer:

Minimum DC current $= 9$ Ampere

Voltage $= 74.862$ V

Explanation:

Here in this questions three resistors are used in series

Resistance of cap circuit

$R_1 =\frac{ 8* 2.3}{6} \\R_1 = 3.067$

Here $2.3$ is the resistance per cap

Resistance of bus wire

$R_2 = \frac{50 * 4.02 }{1000} \\R_2 = 0.201$

Where $4.02$ is the resistance per $1000$ feet of bus wire of gauge 16

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$R_3 = \frac{(2*1000)* 2.525}{1000} \\R_3 = 5.05$

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Total resistance is equal to

$R = R_1 + R_2 + R_3\\R = 3.067 + 0.201 + 5.05 \\R = 8.318$

Current in firing line is equal to

$1.5 * 6\\= 9$

Voltage is equal to product of resistance and current

$= 9 * 8.318\\= 74.862$

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