Electric Field - Practice Questions PDF

Electric Field Do you know how lightning is produced? 2 Lightning can be produced between opposite charges within a cloud, between two or more separate clouds, or between the cloud and the ground. 3 Clouds become negatively charged, which induce pos...

Electric Field Do you know how lightning is produced? 2 Lightning can be produced between opposite charges within a cloud, between two or more separate clouds, or between the cloud and the ground. 3 Clouds become negatively charged, which induce positive charges on the ground. This initiates the discharge of lightning. 4 The formation of lightning is quite fascinating, but a good thing to think about is how these electric charges in the clouds interact with the charges at the ground without even touching. 5 How do charges affect each other when they are not in contact? 6  Describe an electric field as a region in which an electric charge experiences a force Draw electric field patterns due to systems with isolated point charges 7  Use in calculations the relationship between the electric field and the electric force on a test charge 8  Solve problems involving electric charges, dipoles, forces, fields, and flux in contexts such as, but not limited to, systems of point charges, classical models of the atom, electrical breakdown of air, charged pendulums, control of electron and proton beams, electrostatic ink- jet printers 9  State that there are positive and negative charges, and that charge is measured in coulombs Predict charge distributions, and the resulting attraction or repulsion, in a system of charged insulators and conductors 10  Define electric field. Relate electric field and electric force. Solve problems involving electric field. Draw electric field patterns due to systems with isolated charges. 11  Field Forces Field forces are forces that act between objects even if they are not in contact. 1. Electrostatic (Coulombic) force 2. Gravitational force 12 How do we define an electric field? 13  Electric Field Electric field is defined as the amount of electric force on a charged body exerted by external charged bodies. Electric field is a way on how charges communicate to one another. 14  Electric Field Consider two charged particles A and B, where A is much bigger than B. 15  Electric Field Because A and B are both charged, they then affect one another. Their interaction is described as repulsion. 16 Electric Field What happens when you remove charged particle B? 17  Electric Field Point P still experiences the force exerted by A, mainly because A always exerts its electric field. 18  Electric Field The presence of electric field around A can be proven by adding a test charge q0 at position P. 19 A charged particle produces an electric field around it. Thus, another charged particle reacts to it by experiencing an electric force. A charge produces an electric field in its surroundings, but this electric field cannot exert a net force on the charge that created it. 20 How are electric force and electric field related to each other? 21  Electric Field and Electric Force In general, we can formally define the electric field at a point P as the electric force (Fe) acting on a positive test charge (q0) placed at that point per unit charge. Since electric force is a vector quantity, we can already deduce that electric field is also a vector quantity. It has an SI unit of newton per coulomb (N/C). 22  What is the relationship between the electric field and the distance of the test charge? 23  Electric Field and Electric Force Recall Coulomb’s law: If we let q1 as the external charge q and q2 as our test charge q0, we have 24  Electric Field and Electric Force Then, we can further rewrite the equation for electric field as The inverse-square law is still applicable to the electric field equation. 25 What is the magnitude of the field at 4 m from a 2.68 nC charge? 26 What is the magnitude of the field at 4 m from a 2.68 nC charge? The electric field is 1.505825 N/C at 4 m away from the charge. 27 How far from a 2 mC charge is a point where the electric field has a value of 4 N/C? 28  How far from a 2 mC charge is a point where the electric field has a value of 4 N/C? At a distance of 2120.14 m or approximately 2.12014 km from the charge, the electric field is 4 N/C. 29 A charged particle of 6 nC is placed on the x-axis. At which position(s) along the x-axis would there be an electric field of 3 N/C? 30  A charged particle of 6 nC is placed on the x-axis. At which position(s) along the x-axis would there be an electric field of 3 N/C? The positions along the x-axis where the electric field is 3 N/C are: 𝑥 = ±4.24 m 31 A 2 nC charge was placed at position (0, 4 m). What is the magnitude of the electric field at position (2 m, 0 m)? 32 A 2 nC charge was placed at position (0, 4 m). What is the magnitude of the electric field at position (2 m, 0 m)? At position (2 m, 0 m), (0, 4 m). the electric field is 0.9 N/C. 33 If a positive charge of 6 nC was placed at (4 m, 0 m), calculate the electric field at position (2 m, 2 m). 34 If a positive charge of 6 nC was placed at (4 m, 0 m), calculate the electric field at position (2 m, 2 m). At position (2 m, 2 m), (4, 0 m). the electric field is 6.74N/C.. 35 How can we represent the existence of an electric field? 36  Drawing Electric Field Lines Single Isolated Charges Draw rays depending on the charge that is being illustrated. For a positive charge, the field lines should be directed away from the charge. 37  Drawing Electric Field Lines Single Isolated Charges Draw rays depending on the charge that is being illustrated. For a negative charge, on the other hand, the field lines will be directed towards it. 38  Drawing Electric Field Lines Dipoles Case 1: Attractive (positive charge and negative charge) 39  Drawing Electric Field Lines Dipoles Case 2: Repulsive (positive charges) 40  Drawing Electric Field Lines Dipoles Case 3: Repulsive (negative charges) 41  Drawing Electric Field Lines Three Basic Rules in Drawing Electric Field Lines 1. Field lines emanate from the positive charge and terminate to the negative charges. 1. Field lines do not intersect at one point. Field lines only meet if the force between the charges is attractive. 1. The density of the lines (number of lines per space) represents the strength of the field. 42 Write T if the statement is true. If false, change the underlined word(s) to make the statement true. 1. Electric field is a scalar quantity. 1. The unit of electric field is N/C2. 1. There is an inverse-square relationship between electric field and distance. 43  Electric field is defined as the amount of electric force on a charged body exerted by external charged bodies. It can also be said that the electric field is the force per unit charge. 44  A charge produces an electric field around it, and a test charge will react to it by experiencing electric force. Electric field is a vector quantity. It can be illustrated using electric field lines. 45  There are three rules in drawing electric field lines: ○ Field lines emanate from positive charge and terminate to negative charges. ○ Field lines do not intersect at one point. They only meet when there is an attractive force. ○ The more space between field lines, the weaker the electric field is. Equal spaces of lines mean there is a uniform electric field. 46  Concept Formula Description You can use two Electric Field equations to define the where electric field. This E is the electric field, equation reflects the Fe is the force relationship between between the charge electric force and and the test charge, electric field. and q0 is the test charge. 47  Concept Formula Description You can use two Electric Field equations to define the where electric field. This E is the electric field, equation shows how to q is the charge that calculate the electric creates the electric field, field when the charge r is the distance between of the particle that sets q and the test charge, up the field and the k is the Coulomb distance of the point constant with a value of 9 ✕ 109 Nm2/C2. charge are given. 48 Can a charged particle be affected by its own electric field? Why? 49