Electroscope Activity Sheet-1 PDF

Preview

Summary

Download Electroscope Activity Sheet-1 PDF

Description

Investigating Charges using Electroscope Virtual Laboratory Without laboratories, men of science are soldiers without arms. - Louis Pasteur Static electricity is the accumulation of electric charge on the surface of a material. It results from the imbalance of electric charges which occurs when electrons are transferred to or removed from a material. Once the material is charged, it can be used to charge another material either by conduction or induction. To detect the presence of an electric charge, a device called an electroscope might be used. In this part of the module, you will explore the Electroscope Interactive Simulation to investigate the induced charge separation and the two ways of charging. Learning Objectives: 1. To investigate how electroscope detect electric charges 2. To differentiate charging by conduction and charging by induction Materials: Simulation Title: Electroscope https://mattcraig.org/sims-910-science/ Procedure: 1. To load the program, select the online simulation entitled “Electroscope” which is 8 th on the list. Once the program is loaded, familiarize yourself with the components of the Net charge simulation. Reset

Electroscope

2. Adjust the slider-bar on the left to give the rod different magnitudes of positive and negative charge.

3. Hit the reset icon on the top right of the simulation to bring the electrons to their original configuration. 4. On the lower left is a button that will switch the electroscope between transparent view (see the electrons) and ordinary view (how it looks in real life). 5. Manipulate the Electroscope Interactive Simulation following the procedure below. ---------------------------------------------------------------------------------------------------------------------Part A. Charging by Conduction 1. Charge the rod positively by moving the slider upward. Drag the rod near the neutral electroscope and until it touches the center of the metal sphere. Observe the charges and the leaves of the electroscope. Record your observations on the data table. 2. Reset the program. This time charge the rod negatively by moving the slider downward. Allow the rod to touch the center of the metal sphere. Observe the charges and the leaves of the electroscope. Record your observations on the data table. Data Table1: Charging by Conduction Charge on Charge on electroscope rod (metal leaf) positive

positive

positive

positive

negative

negative

negative

negative

Observations Describe how the metal leaves moved When the positively-charged (11%) rod was brought near the electroscope the leaves moved away from each other When the positively-charged (25%) rod was brought near the electroscope the leaves moved away from each other. However, the process was faster than the first trial (where 11% positively-charged rod was used) When negatively-charged (11%) rod was brought near the electroscope the leaves moved away from each other. When the negatively-charged (25%) rod was brought near the electroscope the leaves moved away from each other. However, the process was faster than the third trial (where 11% negatively-charged rod was used)

Fig. 1.0. 11% positively-charged rod touching the center of electroscope

Fig. 1.1. 25% positively-charged rod touching the center of electroscope

Fig. 1.2. 11% negatively-charged rod touching the center of electroscope

Fig. 1.2. 25% negatively-charged rod touching the center of electroscope

Part B. Charging by Induction 1. Charge the rod positively by moving the slider upward. Hold the positive rod near the neutral electroscope. See to it that it does not touch the metal sphere. Observe the charges and the leaves of the electroscope. Record your observations on the data table 2. While the rod is still near the electroscope, ground the electroscope by dragging the ground towards the electroscope. Keep the charged rod near the sphere and keep it grounded at the same time. Observe what happens then record your observations. 3. Remove the ground and the rod. Observe. 4. Reset the program. This time charge the rod negatively by moving the slider downward. Hold the negative rod near the neutral electroscope. See to it that it does not touch the metal sphere. Observe the charges and the leaves of the electroscope. Record your observations on the data table 5. While the rod is still near the electroscope, ground the electroscope by dragging the ground towards the electroscope. Keep the charged rod near the sphere and keep it grounded at the same time. Observe what happens then record your observations. 6. Remove the ground and the rod. Observe. Data Table2: Charging by Induction Procedure

Observations Describe how the charges and the metal leaves moved.

The charge in the electroscope remained neutral but the negative charges (electron) moved towards the direction Step 1: holding the positive where the positively charge-rod was located. Moreover, as rod near the electroscope the electrons move, the leaves started to move way from each other. The electrons from the ground entered the electroscope as the electrons neutralizes the positive charge the leaves relax Step 2: holding the positive back from its original position (where to leaves are side by rod near the electroscope side with each other). However, as the electrons continue to while the electroscope is enter the rod and eventually become greater in number than grounded the protons, the leaves started to move away from each other again. The charge in the electroscope remained neutral but the Step 4: holding the negative charges (electron) moved away from where the negative rod near the negatively charge-rod was located. Moreover, as the electroscope electrons move, the leaves also started to move way from each other. Step 5: holding the The electrons from the electroscope move towards the negative rod near the ground and eventually transferred there. The charges in the electroscope started to neutralized causing the leaves to electroscope while the move towards each other again. However, as the electrons electroscope is grounded

continue to enter the ground, the presence of electrons becomes lesser than the protons; thus, breaking the neutral state which resulted the leaves to move away from each other again.

Figure 2.0. 25% positively-charged rod placed near the electroscope

Figure 2.1. 25% positively-charged rod placed near the grounded electroscope

Figure 2.2. 25% negatively-charged rod placed near the electroscope

Figure 2.4. 25% negatively-charged rod placed near the grounded electroscope Guide Questions: 1. How does an electroscope detect the presence of electric charge? Electroscope detect the presence of electric charge by using its leaves which separate when charged. 2. How will you differentiate charging by conduction from charging by induction? Conduction and induction are two different methods of charging. However, there are big difference between the two. In conduction, a system can only be charged by

forming direct contact between a neutral body and a charged body. Meanwhile, in induction charging a neutral body does not require a direct contact with it and a charged body. Moreover, when charging through conduction, the amount of charge decreases due to distribution; on the other hand, through induction the amount of charge remains constant.

CONCLUSION Conduction is process of charging a neutral body by having a direct contact with a charged body. On the other hand, induction is the process of charging a neutral body without having a direct contact with a charged body. Moreover, in conduction there is a change (decrease) in number of charges while in induction the amount of charge remains in constant. Furthermore, the experiment showed that like charges repel each other. This was evident throughout the experiment as the leaves of the electroscope moves away (repel) from each other as they become both positively charged (Fig. 1.0 and Fig. 1.1) or negatively charged (Fig. 1.3 and Fig. 1.4). In addition, the stronger the charge is the stronger it attracts its opposite charge. This was observed in the first part of the experiment as the 25% positively-charged rod seemed to attract the electrons inside the rod faster than the 11% positively-charged rod. Similar phenomenon occurred with the 11% and 25% negatively-charged rod. By further doing the experiment, it can also be concluded that when a positively-charged body is touched with a conducting object (in this experiment it was the ground) then the charge from the conducting material will be attracted and will move toward the body; thus, neutralizing the body. In addition, when a negatively-charged body is touched with a conducting object then its negative charges will be attracted with the conducting material. This consequently causes the negativelycharged body to be neutralized. To summarized, like charges repel each other and opposite charges are attracted to one another. Moreover, conduction is a process of charging a neutral body by having a direct contact with a charged body; while induction is the process of charging a neutral body with making it have a direct contact with a charged body....