Physics Lab Questions Experiment 4 Charge, Field, and Potential 4.1 The Experime
ID: 1602612 • Letter: P
Question
Physics Lab Questions
Experiment 4
Charge, Field, and Potential
4.1 The Experiment: Field Mapping Board
You will use an electric field mapping board shown in Fig. 4.2. On the board is a piece of conducting black paper with a grid marked out in centimeters. There are two electric contacts (one red, one black) also attached to the board. The contacts act as charge sources. The red contact acts a positive charge, and the black contain a negative charge. The contacts are connected to a power supply that charges the contacts. When the contacts are charged there is an electric field on the surface of the black conduct- ing paper. Using a pair of field probes and voltmeter you can measure the direction and strength of the electric field on the surface of the paper.
1. What do the electric field lines represent? (2 points)
2. What are the primary similarities and differences between the electric fields surrounding each electric contacts on the field board; i.e, the positive and negative contacts? (2 points)
3. Where was the electric field strongest for each electric contact? Explain your answer. (2 points)
4. Would the shape of the electric field lines for the two electric contacts change if you increased the voltage across the electric contacts on the field board? Explain your answer. (2 points)
5. What can be said about the voltage at each point of a line of equipotential? (2 points)
6. If you positioned the two probes along an equipotential line; i.e.; parallel to the equipotential line, what value of electric field would you measure? Explain your answer (2 points)
44.9 deg Charges And Fields +1 nC 1 nC Sensors -2.303 V Electric Field Direction only M voltage Y Values Grid PIETExplanation / Answer
(1) electric field lines represent the electric fleld geometrically . the electric field line represents a line straight or curved along which a unit positive charge moves if it palced in the presence of a source charge.
(2) eletric field lines due to both positive and negative charges represent eletric field.
DIFFERENCE
eletric field lines due to a positive charge move outwards away from the charge while as the lines of force due to negative charge charge move inwards(towards the negative charge)
(3)electric field is strongest where the electric field lines are closer. for both charges, the electric field is stronger near the charge(contact).
(4)if we increase the voltage ,the electric filed intensity will increase .That means the eletric field lines will come closer to each other but the shape of lines will remain same.
(5) voltage at each point of the equipotential line is same