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3 years ago

Prove 1/P = 1/P1 + 1/P2

Physics

1 answer:

Sati [7]3 years ago

7 0

Answer:

Proof:

|----------(R1)-------------(R2)---------|

Let the resistances be R1 , R2 connected in series. And the potential difference be V ;

We know that :

P1 = V²/R1 ..........(1) and

P2 = V²/R2 ...........(2)

In series combination , the net resistance is the algebraic addition of individual resistance :

R = R1 + R2

=> V²/P = V²/P1 + V²/P2

=> 1/P = 1/P1 + 1/P2

Explanation:

Copied it from a different brainly question that is this question. Please try to find it on brainly instead of asking it'd make it much easier.

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where

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mg is the weight of the string, which points downward, with

m = 0.158 kg being the mass of the ball

g = 9.8 m/s^2 being the acceleration due to gravity

$m \frac{v^2}{R}$ is the centripetal force, which points upward, with

v = 5.22 m/s being the speed of the ball

R = 1.1 m being the radius of the circular trajectory

Substituting numbers and re-arranging the formula, we find T:

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$T=m\frac{v^2}{R}$

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And substituting the numerical values and re-arranging it, we find

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4) 3.3 m/s

The minimum velocity for the ball to keep the circular motion occurs when the centripetal force is equal to the weight of the ball, and the tension in the string is zero; therefore:

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3 years ago

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Answer:

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Explanation:

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The answer is 0.245N.

<h3>What is kinetic energy?</h3>

A particle or an item that is in motion has a sort of energy called kinetic energy. An item accumulates kinetic energy when work, which involves the transfer of energy, is done on it by exerting a net force.
Kinetic energy comes in five forms: radiant, thermal, acoustic, electrical, and mechanical.
The energy of a body in motion, or kinetic energy (KE), is essentially the energy of all moving objects. Along with potential energy, which is the stored energy present in objects at rest, it is one of the two primary types of energy.
Explain that a moving object's mass and speed are two factors that impact the amount of kinetic energy it will possess.

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