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Step2247 [10]
3 years ago
10

n the railroad accident, a boxcar weighting 200 kN and traveling at 3 m/s on horizontal track slams into a stationary caboose we

ighting 400 kN. The collision connects the caboose to the car, and then both move together and you have found the final velocity. Apparently, initial kinetic energy of the system changes (in part, because of friction present). How much energy (in kJ) is transferred from kinetic energy to other forms of energy (e..g., thermal) in the collision
Physics
1 answer:
USPshnik [31]3 years ago
7 0

Answer:

ΔK = -6 10⁴ J

Explanation:

This is a crash problem, let's start by defining a system formed by the two trucks, so that the forces during the crash have been internal and the moment is preserved

initial instant. Before the crash

        p₀ = m v₁ + M 0

final instant. Right after the crash

        p_f = (m + M) v

        p₀ = p_f

        mv₁ = (m + M) v

        v = \frac{m}{m+M} \  v_1

     

we substitute

        v = \frac{20}{20+40}   3

        v = 1.0 m / s

having the initial and final velocities, let's find the kinetic energy

        K₀ = ½ m v₁² + 0

        K₀ = ½ 20 10³ 3²

        K₀ = 9 10⁴ J

        K_f = ½ (m + M) v²

        K_f = ½ (20 +40) 10³  1²

        K_f = 3 10⁴ J

the change in energy is

       ΔK = K_f - K₀

       ΔK = (3 - 9) 10⁴

       ΔK = -6 10⁴ J

The negative sign indicates that the energy is ranked in another type of energy

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Answer:

The magnitude of the voltage is 2.27\times10^{-4}\ V and the direction of the current is clockwise.

Explanation:

Given that,

Number of turns = 9

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Time t = 0.14 s

We need to calculate the flux

Using formula of flux

\phi=NAB

Put the value into the formula

\phi=9\times\pi\times(1.5\times10^{-2})^2\times0.5

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We need to calculate the emf

Using formula of emf

\epsilon=-\dfrac{d\phi}{dt}

\epsilon=-\dfrac{0.003180}{0.14}

\epsilon =-0.000227\ V

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Negative sign shows the direction of current.

Hence, The magnitude of the voltage is 2.27\times10^{-4}\ V and the direction of the current is clockwise.

8 0
3 years ago
A child throws a ball with an initial speed of 8.00 m/s at an angle of 40.0° above the horizontal. The ball leaves her hand 1.00
vivado [14]

Answer:

7.5 m

Explanation:

v = initial speed of the ball = 8 m/s

\theta = angle of launch = 40° deg

Consider the motion along the vertical direction :

v_{oy} = initial velocity along vertical direction = v Sin\theta = 8 Sin40 = 5.14 m/s

a_{y} = acceleration along vertical direction = - 9.8 m/s²

t = time of travel

y = vertical displacement = - 1 m

Using the kinematics equation

y = v_{oy}t + (0.5)a_{y}t^{2}

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t = 1.22 sec

Consider the motion along the horizontal direction :

v_{ox} = initial velocity along horizontal direction = v Sin\theta = 8 Cos40 = 6.13 m/s

a_{x} = acceleration along vertical direction = 0 m/s²

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x = horizontal displacement = ?

Using the kinematics equation

x = v_{ox}t + (0.5)a_{x}t^{2}

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3 years ago
In transduction, the cochlea is part of this structure:
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Answer:

wats up

Explanation:

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2 years ago
Cynthia forgot to put the fabric softener in the wash. As her socks tumbled in the dryer, they became charged. If a small piece
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Answer:

E = 24000 N/C = 24 KN/C

Explanation:

The electric field experienced by a test charge is given by the following formula:

E = \frac{F}{q}\\\\

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Therefore, using these values in the equation, we get:

E = \frac{3\ x\ 10^{-6}\ N}{1.25\ x\ ^{-10}\ C}\\\\

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The term for the principal that an object in motion remains in motion until it is met by an outside force is called inertia

Newton's first law states that if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force .This principal is named as inertia .

Every matter have inertia , a property to remain in that very position until unless it is been forced on them to change their position .

Inertia is a property of matter that causes it to resist changes in velocity (speed and/or direction). According to Newton's first law of motion, an object with a given velocity maintains that velocity unless acted on by an external force. Inertia is the property of matter that makes this law hold true.

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