Electroscope

What is an electroscope? Draw a labelled diagram of an electroscope and explain its working.

How will you show that like charges repel and unlike charges attract each other?

When a plastic rod rubbed with wool is brought near the knob of a negatively charged gold-leaf electroscope, the gold leaves:

1. Dilate

2. Contract

3. Start oscilating

4. Collapse completely

1. It depends on the material the electroscope is made of.

2. Neutral

3. Positive

4. Negative

Question 9

Describe with the help of a diagram an instrument which can be used to detect a charged body.

Name the device to detect electric charge on a body.

How will you use a gold leaf electroscope to find out whether a body is charged or uncharged?

Why is gold used as leaf electroscope?

1. It is easy to procure

2. It is used due to its colour and reflectivity

3. It does not corrode easily and can be made into very thin sheets.

4. Gold leaves are expensive and are a status symbol

1. Induction

2. Conduction

3. Photon Emission

4. Galvanization

How will you use a pith ball electroscope to find out whether the charge on a charged body is positive or negative?

Draw a labelled diagram of a gold leaf electroscope and describe its construction.

Which one of the following devices is used to detect electric charge on an object?

1. Seismograph

2. Seismometre

3. Richter scale

4. Electroscope

An electroscope is given a positive charge, causing its foil leaves to separate. When an object is brought near the top plate of the electroscope, the foils separate even further because, ___.

1. the object is positively charged

2. None of the above

3. the object is electrically neutral

4. the object is negatively charged

An electroscope is a device which is used to find if an object is

1. charged

2. magnetic

3. hot

4. cold

1. electrometer
2. seismograph
3. electroscope
4. ritcher scale

A neutral electroscope is touched with a negatively charged rod. What is the charge on the electroscope after the rod is removed?

1. Positive

2. It stays neutral

3. Negative

4. It depends on the contact time

The rod in a gold leaf electroscope is made up of :

1. Brass

2. Gold

3. Aluminium

4. Silver

Describe an experiment to demonstrate that there are two kinds of charges.

Describe a pith ball electroscope. How can you use it to test whether a body is charged or uncharged?

1. The positive charge flows from the ground to the electroscope.
2. Negative charge flows from the ground to the electroscope.
3. Negative charge flows from the electroscope to the ground.
4. Positive charge flows from the electroscope to the ground.

A negatively charged ebonite rod is touched with the disc of a negatively charged gold leaf electroscope. What will be your observation?

When a charged rod is touched with the disc of a positively charged gold leaf electroscope, it is observed that the divergence of leaves decreases. What is the kind of charge on the rod?

When an object is touched with the metal top of an electroscope, its aluminium leaves diverge. What concludion do you get from this observation?

What is the name of the device shown in the figure?

1. Coal electroscope
2. Pith ball electroscope
3. Gold leaf electroscope
4. Needle electroscope

An electroscope can be charged by which one of the following methods?

1. Radiation

2. Convection

3. Conduction

4. All of the above.

A positively charged glass rod is touched with the disc of an uncharged gold leaf electroscope. What will be your observation?

A charged glass rod attracts a charged plastic straw.

1. True
2. False

How will you find out whether an object is charged or not ?

1. move away from the body
2. oscillate like a pendulum
3. move toward the body
4. become hot with time

What will you observe when the metal top of an electroscope is touched with:

(a) a positively charged object?

(b) a negatively charged object?