Answer the

A.1 Different Values of Relative Permittivity (r) Based on the Material

Name: Grade & Section: Score: School: Teacher: Subject: General Physics 2 LAS Writer: JAN JEFFREY R. CAMINA Content Editor: RETCHIE JOY. PISANA EDA A. FALE Learning Topic: Effect of the Construction of Simple Capacitors to its Capacitance; Quarter 3-Week 3 LAS 2 Learning Targets: Deduce the effects of simple capacitors (e.g., parallel plate, spherical, cylindrical) on the capacitance, charge, and potential difference when the size, potential difference, or charge is changed. Reference(s): Young, H. and Freedman, R., 2012. University Physics with Modern Physics. 13th ed. 1301 Sansome Street, San Francisco, CA, 94111: Pearson Education, Inc., pp 788-792. Effect of the Construction of Simple Capacitors to its Capacitance Conductive Plates Capacitors A capacitor is a device that is used to store electrical potential energy. It has many uses, including tuning the frequency of radio receivers, eliminating sparking in automobile ignition systems, and storing energy in electronic flash units. A typical design for a capacitor consists of two parallel metal plates separated by a small distance or sometimes Dielectric an insulating material called a dielectric. Each capacitor plate carries a charge of the same magnitude, one positive and the other negative. The ability of a capacitor to store Figure 1. Typical Parallel Metal Plate Capacitor. a charge on its conductive plates is its capacitance value measured in Farads (F). Formula for Capacitance (C): The magnitude of the charge (Q) on each plate of a capacitor is directly proportional to the magnitude (V) of the potential difference between C = "/Ay : SI unit is Coulomb per Volt(C/V) or the plates. Farad (F) Electric Field (E) Between the Plates: The magnitude of the Electric field (E) between plates is given by the EGETA ' i F = surface charge density formula surface charge density () divided by area (A) of one of the metal plates or charge (Q) divided by the product of the absolute permittivity (co), .= absolute permittivity relative permittivity (Er) and area (A) of one of the metal plates. Where, of &. = &,= absolute permittivity 8.85 x10"12Nm'/C. (refer to attachment A.1 for the values of Er) A = area of one of the metal plates The magnitude of the electric potential difference (4V) between the two plates Electric Potential Difference (AV) Between the Plates: is the product of Electric field (E) and the distance (d) between the two metal plates. Furthermore, it can also be equated, by using the previous equation, to the product of AV = Ed = /E.E,A Charge (Q) and distance (d) divided by the product of absolute permittivity (co), relative permittivity (Er) and area (A). Different Constructions of the Capacitors with their Capacitance Values: Conductive Plates 2TEErL C = 4neger 72-ri In(#2/ RX) C = Eger "/ d' E = E = - Q Dielectric 4TE Er (12-11)2 Cylindrical AV = - Q(12-1) AV = (RZ) 2 TEOEr AV = "/ AEGEr Parallel-Plate Spherical A = charge per unit area (C/m?)A.1 Different Values of Relative Permittivity (Er) Based on the Material Material Er Material Er Vacuum Quartz 5 Freon Diamond 5-6 Air 1.0005 Wet soil 5-15 Styrofoam 1.03 Mica (ruby) 5.4 Polyurethane foam 1.1 Steatito 5.8 Paper 1.3-3 Sodium chloride (NaCI) 5.9 Wood 2-5 Porcelain 6 Dry soil 2-6 Neoprene 6.6 Paraffin 2.1 Silicon nitride (SigNA) 7.2 Teflon 2.1 Marble 8 Vaseline 2.16 Alumina (Al203) 8.8 Polyethylene 2.25 Animal and human muscle 10 Oil 2.3 Silicon (Si) 11.9 Rubber 2.4-3 Gallium arsenide 13 Polystyrene 2.56 Germanium 16 PVC 2.7 Ammonia (liquid) 22 Amber 2.7 Alcohol (ethyl) 25 Plexiglass 3.4 Tantalum pentoxide 25 Nylon 3.6-4.5 Glycerin 50 Fused silica (SiO2) 3.8 Ice 75 Sulfur Water 81 Glass 4-10 Rutile (Tio2) 89-173 Bakelite 4.74 Barium titanate (BaTio3) 1,200 * For static or low-frequency applied electric fields, at room temperature. A.2 Rubrics for the Activity Fully meet expectations Minimally meet the Did not meet the expectations expectations Illustration Precise and summarizes The illustration summarizes The illustration does not the target topic. some parts of the target meet the target topic. topic. (3 points) (1 point) (2 points) Explanation Precise and summarizes The explanation summarizes The explanation does not the target topic. some parts of the target meet the target topic. topic. (2 points) (0) (1 point)