# Electric Fields: Supporting a 4kg Chicken

• Lalitha
In summary: ?a. no work is done and the energy stored stays constant.b. work is done, increasing the amount of stored energy in the capacitor.c. work is done, decreasing the amount of energy stored in the capacitor.
Lalitha
Hello Sir ,
i am new to the site and so is not familar of that but i have question and i found u online so wish u to help me with that.

Electric forces are used to accelerate small particles (like ink particles in a printers) but consider electrostatic action on macroscopic objects .Suppose that a 4 kg chicken were to be supported by a vertically upwardly directed electric field .Since the amximum E strength in air is about 3*10^6.The net charge on each chicken would be unreasonably large since it must be least.

a) 1.3*10^-6

b)1.3*10^-5

c)-1.3*10^-5

d)7.7*10^4

none

Last edited by a moderator:

In a static situation, the upward electric force must be equal and opposite the weight of the mass being suspended.

thanks a lot sir i got that.I am very Thankful for your help .

Astronuc said:

In a static situation, the upward electric force must be equal and opposite the weight of the mass being suspended.

as we are said that the electric force is equal to mass but in oppostie direction then the force that makes the body stantionary in an electric field is F=-mg=-4*10 (g=9.8m/sec^2=10 app),

And as E=3*10^6 and using the realtion that F=qE

we get q=F/E=-4*10/(3*10^6)=-1.3*10^-5

Lalitha said:
as we are said that the electric force is equal to mass but in oppostie direction then the force that makes the body stantionary in an electric field is F=-mg=-4*10 (g=9.8m/sec^2=10 app),

And as E=3*10^6 and using the realtion that F=qE

we get q=F/E=-4*10/(3*10^6)=-1.3*10^-5
Be careful here.

The force of gravity is down so the force of the electric field must be up, so Fe = -Fg, so if Fg = -40N, the Fe = 40 N. What does that indicate about the polarity of the charge?

EDIT: beaten by Astro

Astronuc said:
Be careful here.

The force of gravity is down so the force of the electric field must be up, so Fe = -Fg, so if Fg = -40N, the Fe = 40 N. What does that indicate about the polarity of the charge?

Sir here as we consider the force of gravity so it need to be +40N NA SIR as we have given that m=4kg,
and f=mg =4*10=40,
and Fe=-Fg=-40.

Is that not right Sir ?

Hello Sir Plz let me know am i correct or going wrong there mean as fg=mg=4*10=40 and Fe=-Fg=-40N

Fe=-Fg= 40N

The gravitational force is downward, and by convention, that is negative.

Acceleration is a vector as is force. By convention a downward vector is negative.

The acceleration of gravity is $$\vec{a}\,=\,-9.81 \hat{j}\,m/s^2$$, where $$\hat{j}$$ is the unit vector in the vertical orientation and is taken as positive.

Ok thanks a lot for that sir .I got it now .

Kurdt said:
EDIT: beaten by Astro

The plates are connected to a battery and then the connection is removed so the two plates are left charged and isolated. If a dielectric material such as a sheet of glass is inserted between the plates:

a. no work is done and the energy stored stays constant.
b. work is done, increasing the amount of stored energy in the capacitor.
c. work is done, decreasing the amount of energy stored in the capacitor.

Plz can anybody help me with this one

## 1. What is an electric field?

An electric field is an area around a charged object or group of objects where an electric force is present. This force can either attract or repel other charged objects within the field.

## 2. How is an electric field created?

An electric field is created by a charged object, such as a particle or an electron, which exerts a force on other charged objects in its surroundings. The strength of the electric field depends on the magnitude of the charge and the distance from the charged object.

## 3. How does an electric field support a 4kg chicken?

The electric field created by the Earth's surface attracts the positively charged protons in the chicken's body, while repelling the negatively charged electrons. This creates a force that counteracts the force of gravity, allowing the chicken to stay suspended in the air.

## 4. What is the maximum weight that can be supported by an electric field?

The maximum weight that can be supported by an electric field is dependent on the strength of the electric field and the charge of the object. In the case of a 4kg chicken, the strength of the electric field created by the Earth's surface is enough to support its weight.

## 5. How does the size of the charged object affect the electric field?

The size of the charged object does not affect the strength of the electric field, but it does affect the distribution of the electric field. A larger charged object will have a wider area of influence, while a smaller charged object will have a more concentrated electric field. However, the strength of the electric field at a specific distance from the charged object will remain the same regardless of its size.

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