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3 years ago

What is the sprinters output at 2.0 s, 4.0 s and 6.0 s?

Physics

1 answer:

kari74 [83]3 years ago

5 0

A 59 kg sprinter, starting from rest, runs 47 m in 7.0 s at constant acceleration.?

What is the sprinter's power output at 2.0 s, 4.0 s, and 6.0 s?

Instantaneous Power is the force times velocity

P = Fv

Because the acceleration is constant, the force will be constant as well

F = ma

P = mav

for constant acceleration, the velocity at each time is found using

v = at

P = ma(at) = ma²t

find the acceleration using kinematic equation

s = ½at²

a = 2s/t²

a = 2(47) / 7.0²

a = 1.918 m/s²

P(2.0) = 59(1.918²)2.0 = 434.25 W = 0.43 kW

P(4.0) = 59(1.918²)4.0 = 868.51 W = 0.87 kW

P(6.0) = 59(1.918²)6.0 = 1302.76 W = 1.3 kW

I hope this helped.

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A sample of helium (He) occupies 8.0 liters at 1 atm and 20.0◦C. What pressure is necessary to change the volume to 1.0 liters a

nevsk [136]

Apply the combined gas law

PV/T = const.

P = pressure, V = volume, T = temperature, PV/T must stay constant.

Initial PVT values:

P = 1atm, V = 8.0L, T = 20.0°C = 293.15K

Final PVT values:

P = ?, V = 1.0L, T = 10.0°C = 283.15K

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3 years ago

A projectile of mass 1.800 kg approaches a stationary target body at 4.800 m/s. The projectile is deflected through an angle of

Artyom0805 [142]

Answer:

P = 5.22 Kg.m/s

Explanation:

given,

mass of the projectile = 1.8 Kg

speed of the target = 4.8 m/s

angle of deflection = 60°

Speed after collision = 2.9 m/s

magnitude of momentum after collision = ?

initial momentum of the body = m x v

= 1.8 x 4.8 = 8.64 kg.m/s

final momentum after collision

momentum along x-direction

P_x = m v cos θ

P_x = 1.8 x 2.9 x cos 60°

P_x = 2.61 kg.m/s

momentum along y-direction

P_y = m v sin θ

P_y = 1.8 x 2.9 x sin 60°

P_y = 4.52 kg.m/s

net momentum of the body

$P = \sqrt{P_x^2 + P_y^2}$

$P = \sqrt{4.52^2 + 2.61^2}$

P = 5.22 Kg.m/s

momentum magnitude after collision is equal to P = 5.22 Kg.m/s

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3 years ago

The density of aluminum is 2.7 × 103 kg/m3 . the speed of longitudinal waves in an aluminum rod is measured to be 5.1 × 103 m/s.

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Creates an image that appears upside down behind the focal point

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mylen [45]

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We have to calculate the net force on Earth due to Venus, Jupiter and Saturn when they are in one line. It means when they are the closest distance.

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Mass of Saturn, Ms = 95.1 Me

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where 1 AU = 1.5 × 10¹¹ m

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3 years ago

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