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2 years ago

5

Calculate the force a 70.0-kg high jumper must exert on the ground to produce an upward acceleration 4.00 times the acceleration

due to gravity. Explicitly show how you follow the steps in the Problem-Solving Strategy for Newton’s laws of motion.

1 answer:

worty [1.4K]2 years ago

3 0

Answer:

3433.5 N

Explanation:

g = Acceleration due to gravity = 9.81 m/s²

m = Mass of person = 70 kg

According to the question

a = Acceleration

$4g=4\times 9.81\\\Rightarrow a=39.24\ m/s^2$

Balancing the forces we have

$F-w=ma\\\Rightarrow F=ma+w\\\Rightarrow F=ma+mg\\\Rightarrow F=m(a+g)\\\Rightarrow F=70(39.24+9.81)\\\Rightarrow F=3433.5\ N$

The required force is 3433.5 N

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Kazeer [188]

Answer:

$i(t) = -\frac{q_0C}{R}e^{-t/RC}$

Explanation:

If the voltage across a capacitor is given by

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2 years ago

A proposed space elevator would consist of a cable stretching from the earth's surface to a satellite, orbiting far in space, th

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To solve this problem we will apply the concepts related to energy conservation. Here we will use the conservation between the potential gravitational energy and the kinetic energy to determine the velocity of this escape. The gravitational potential energy can be expressed as,

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From the conservation of energy:

$\frac{1}{2} mv^2 = \frac{GMm}{d}$

Rearranging to find the velocity,

$v = \sqrt{\frac{2Gm}{d}} \rightarrow$ Escape velocity at a certain height from the earth

If the height of the satellite from the earth is h, then the total distance would be the radius of the earth and the eight,

$d = r+h$

$v = \sqrt{\frac{2Gm}{r+h}}$

Replacing the values we have that

$v = \frac{2(6.67*10^{-11})(5.972*10^{24})}{6.378*10^6+56*10^6}$

$v = 3.6km/s$

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2 years ago

A slide whistle is an open-closed tube with an adjustable plunger that changes the length. You are playing the slide whistle and

Serjik [45]

Answer:

df / ft = -n 12 n= 1, 3, 5, ...

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v = λ f

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λ₁ = 4L

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λ₃ = 4L / 3

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λₙ = 4L / n

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We substitute and clear in the first equation

f = v n / 4L n = 1, 3, 5,…

Let's use derivatives to find the frequency change

df / dt = v n /4 dL⁻¹ / dt

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We replace

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Let's calculate

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2 years ago

At one point in the rescue operation, breakdown vehicle A is exerting a force of 4000 N and breakdown vehicle B is exerting a fo

lukranit [14]

Answer:

1.) Magnitude = 5596 N

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Sum of the forces in the X - component will be 4000 × cos 45 = 2828.43 N

Sum of the forces in the Y - component will be 2000 + ( 4000 × sin 45 )

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The resultant force R will be

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R = sqrt ( 2828.43^2 + 4828.43^2 )

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The direction will be

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Substitute Y and X into the formula

Tan Ø = 4828.43 / 2828.43

Tan Ø = 1.707106

Ø = tan^-1( 1.707106 )

Ø = 59.64 degree

Therefore, approximately, the magnitude and direction of the resultant force on the truck are 5596 N and 60 degree respectively.

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2 years ago

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Julli [10]

Answer:

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we know that

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Putting all value to get rate of emission

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2 years ago