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4 years ago

How do you change the currents in a circuit

1 answer:

4 0

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Eddy Current Testing

Introduction
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Current Flow and Ohm's Law

Ohm's law is the most important, basic law of electricity. It defines the relationship between the three fundamental electrical quantities: current, voltage, and resistance. When a voltage is applied to a circuit containing only resistive elements (i.e. no coils), current flows according to Ohm's Law, which is shown below.

I = V / R

Where:

I =

Electrical Current (Amperes)

V =

Voltage (Voltage)

R =

Resistance (Ohms)

Ohm's law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Therefore, if the voltage is increased, the current will increase provided the resistance of the circuit does not change. Similarly, increasing the resistance of the circuit will lower the current flow if the voltage is not changed. The formula can be reorganized so that the relationship can easily be seen for all of the three variables.

The Java applet below allows the user to vary each of these three parameters in Ohm's Law and see the effect on the other two parameters. Values may be input into the dialog boxes, or the resistance and voltage may also be varied by moving the arrows in the applet. Current and voltage are shown as they would be displayed on an oscilloscope with the X-axis being time and the Y-axis being the amplitude of the current or voltage. Ohm's Law is valid for both direct current (DC) and alternating current (AC). Note that in AC circuits consisting of purely resistive elements, the current and voltage are always in phase with each other.

Exercise: Use the interactive applet below to investigate the relationship of the variables in Ohm's law. Vary the voltage in the circuit by clicking and dragging the head of the arrow, which is marked with the V. The resistance in the circuit can be increased by dragging the arrow head under the variable resister, which is marked R. Please note that the vertical scale of the oscilloscope screen automatically adjusts to reflect the value of the current.

See what happens to the voltage and current as the resistance in the circuit is increased. What happens if there is not enough resistance in a circuit? If the resistance is increased, what must happen in order to maintain the same level of current flow?

You might be interested in

You live on a planet far from ours. "Based on extensive communication with a physicist on earth", you have determined that all l

Ugo [173]

Answer:

8.56 m/s2

Explanation:

Using law of energy conservation while taking into account of the rotational and translation kinetic energy, when the solid cylinder rolls down the incline we have the potential energy converted to kinetic energy:

$E_p = E_{kv} + E_{k\omega}$

$mgh = mv^2/2 + I\omega^2/2$

where m is the mass, $I = mr^2/2$ is the moments of inertia of the solid cylinder $\omega = v / r$ is the angular speed of the cylinder

$mgh = mv^2/2 + \frac{mr^2}{2}\frac{(v/r)^2}{2}$

$mgh = mv^2/2 + mv^2/4 = 3mv^2/4$

$h = 3v^2/(4g)$

So if you plot a liner chart of h vs $v^2$ and get a slope of 6.42 then that means 3/(4g) = 6.42 so $g = 6.42*4/3 = 8.56 m/s^2$

The gravitational acceleration on this planet is 8.56 m/s2

3 0

4 years ago

Why does a gram of gold have the same density of a kilogram of gold

raketka [301]

A gram of gold's density is g/ml. If the mass is multiplied by 1000 to get to kg, so is ml. This gives kg/liter as the density. For example, if the density was 2g/ml. the density would still be 2kg/l.

8 0

3 years ago

When you blink your eye, the upper lid goes from rest with your eye open to completely covering your eye in a time of 0.024 s.

dusya [7]

a) Distance moved by the top lid during a blink: 1 cm (estimate)

b) The acceleration is $34.7 m/s^2$

c) The final speed is 0.83 m/s

Explanation:

For the purpose of this problem, we can estimate the size of the eye from the top lid to the bottom lid to be 1 cm, so this is the distance moved by the top lid during a blink.

Assuming the motion of the eyelid to be at constant acceleration, we can find the acceleration by using the following suvat equation:

$s=ut+\frac{1}{2}at^2$

where

s is the distance covered

u is the initial velocity

t is the time

a is the acceleration

For the eyelid, we have:

u = 0 (it starts from rest)

s = 1 cm = 0.01 m is the distance covered

t = 0.024 s is the time taken

Solving for a, we find the acceleration:

$a=\frac{2s}{t^2}=\frac{2(0.01)}{0.024^2}=34.7 m/s^2$

The final speed of the upper eyelid can be found by using another suvat equation:

$v=u+at$

where

v is the final speed

u is the initial speed

a is the acceleration

t is the time

For the eyelid in this problem, we have

u = 0

$a=34.7 m/s^2$

t = 0.024 s

Substituting, we find the final speed:

$v=0+(34.7)(0.024)=0.83 m/s$

Learn more about accelerated motion:

brainly.com/question/9527152

brainly.com/question/11181826

brainly.com/question/2506873

brainly.com/question/2562700

#LearnwithBrainly

4 0

3 years ago

Why do planets orbit the sun (why don't they crash into the sun)?

Jobisdone [24]

Newton realized that the reason the planets orbit the Sun is related to why objects fall to Earth when we drop them. The Sun's gravity pulls on the planets, just as we now understand Earth's gravity pulls down anything that isn't held up by some other force

5 0

3 years ago

The resistance of an object to change its dynamic state called

aleksandr82 [10.1K]

Inertia is the correct answer!

5 0

3 years ago