Gold Leaf Electroscope

  Contents

• Introduction
• Electroscope
• Gold leaf electroscope
• Working of gold leaf electroscope
• Uses of gold leaf electroscope
• Steps to make an electroscope with a diagram

Introduction

The gold-leaf electroscope was developed by British clergyman and physicist Abraham Bennet in the year 1787. This electroscope is more sensitive than a pith ball electroscope and straw blade electroscopes. It is used in electrostatics to show the magnitude and polarity of the charged entities. It is stored in a warm dry environment. It is also used with a zinc plate to illustrate the photoelectric effects.

What is an electroscope?

An electroscope is an early instrument used to detect the presence of an electric charge on a body. It detects the charge by the movement of a test object due to Coulomb electrostatic force on it.

What is a gold-leaf electroscope?

It is a simple instrument to detect charge on a body. It shows how much charge present on a body. It also detects and measures the static electricity or voltage.

How does a gold-leaf electroscope works?

It consists of a metal rod housed in a box, with two thin gold leaves attached to its bottom end. When a charged object touches the metal knob at the top of the rod, charge flows on to the leaves and they diverge. The degree of divergence is an indicator of the amount of charge.

What is the use of a gold-leaf electroscope?

It is simply used to detect the amount of charge present on a body. It shows the presence and magnitude of a charge by applying a charge to the top of a metal knob of the gold leaf electroscope.

How to make an electroscope with steps and diagram?

Materials required:

• Thin aluminium curtain rod, one large bottle, one cork, thin aluminium foil (about 6   cm), a paper scale

Steps:

• Take a thin aluminium curtain rod with ball ends fitted for hanging the curtain.

• Cut out a piece of length about 20 cm with the ball at one end and flatten the cut end.

• Take a large bottle that can hold this rod and a cork which will fit in the opening of the bottle.

• Make a hole in the cork sufficient to hold the curtain rod tightly.

• Slide the rod through the hole in the cork with the cut end on the lower side and ball projecting above  the cork.

• Fold a small thin aluminium foil in the middle and attach it to the flattened end of the rod by cellulose  tape. This forms the leaves of your electroscope.

• Fit the cork in the bottle with about 5 cm of the ball end projecting above the cork.

• Put a paper scale inside the bottle to measure the separation of leaves. The separation is a rough  measure of the amount of charge on the electroscope.