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Sergio039 [100]
2 years ago
8

The average marathon runner can complete the 42.2-km distance of the marathon in 3 h and 30 min. If the runner's mass is 85 kg,

what is the runner's average kinetic energy during the run
Physics
1 answer:
Semenov [28]2 years ago
5 0

Answer:

the runner's average kinetic energy during the run is 476.96 J.

Explanation:

Given;

mass of the runner, m = 85 kg

distance covered by the runner, d = 42.2 km = 42,200 m

time to complete the race, t = 3 hours 30 mins = (3 x 3600s) + (30 x 60s)

                                                                               = 12,600 s

The speed of the runner, v = d/t

                                          v = 42,200 / 12,600

                                          v = 3.35 m/s

The runner's average kinetic energy during the run is calculated as;

K.E = ¹/₂mv²

K.E = ¹/₂ × 85 × (3.35)²

K.E = 476.96 J

Therefore, the runner's average kinetic energy during the run is 476.96 J.

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Evgesh-ka [11]

Answer:

S = \dfrac{1}{2.5}

Explanation:

given,

side slope = 1 : 1

hydraulic depth(y) = 5 ft

bottom width (b)= 8 ft

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n = 0.013

slope of channel = ?

R = \dfrac{A}{P}

R = \dfrac{y(b + xy)}{b+2y\sqrt{1+x^2}}

R = \dfrac{5(8+ 5)}{8+2\times 5\sqrt{1+1^2}}

R = 4.69 m

using manning's equation

Q = \dfrac{1}{n}AR^{2/3} S^{1/2}

2312= \dfrac{1}{0.013}\times (5(8+5))\times 4.69^{2/3} S^{1/2}

2312=14009.37\times S^{1/2}

S = 0.406

S = \dfrac{1}{2.5}

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3 years ago
Determine a formula for the acceleration of the system in terms of mA, mB, θ, and g. Ignore the mass of the cord and pulley. Exp
jekas [21]

Answer:

a=\frac{mBg-mAgSin\theta}{mA+mB}

Explanation:

Given two mass on an incline code mA and mB and an angle of inclination \theta. g. Assume that mA is the weight being pulled up and mB the hanging weight.

-The equations of motion from Newton's Second Law are:

mBg-T=mBa where a is the acceleration.

#Substituting for T (tension) gives:

mBg-mAsin\theta-mAa=mBa

#and solving for a:

a=\frac{mBg-mAgSin\theta}{mA+mB} which is the system's acceleration.

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Identify two factors you must know to describe the motion of an object along a straight line
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Stolb23 [73]

Answer: True

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As current passes through an inductor overtime it tends to store current in the form of magnetic field. Therefore the electric-power industry can store energy in large Inductors.

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3 years ago
The space shuttle usually orbited Earth at altitudes of around 300.0 km. 1) Determine the time for one orbit of the shuttle abou
777dan777 [17]

Answer:

Explanation:

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= 6300 + 300 = 6600 km

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v₀ = √gR , ( if height  is small with respect to radius )

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= 24 x 60 / 85.9

= 16.76

or 17 sunrises.

3 0
3 years ago
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