14 Current of Electricity Tutorial

(c) W hat is its resistance under these operating conditions? (b) A t w hat rate is electrical energy dissipated in the bulb w hen it is operating at its rated voltage? (a) H ow m uch charge flows through the bu©¥b in 1 . 0 hour w hen it is operating at its rated cu©¥T ent? P 1 . A torch is rated as ' 2 . 5 V , 0 . 030 A T . S elf - P ractice w u e stio n s 5 12 . S tate the m axim um power theorem . 5 11 . H ow does the internal resistance of a battery affect its term ina©¥ p . d. A n d output pow eť ? resistor in term s of R ? If the circuit elem ent is a resistor of resistance R , w h a t is the electric power delivered to the passing through it, w hat is the electric power P delivered to or extracted from the circuit elem ent? F or an electric circuit elem ent w ith potential difference V be©¥w een its term ina©¥s and current !5 10 . 5 9 . S ketch the tem perature characteristic of a therm istor. sem iconductor diode and a filament ©¥am p . 5 8 . S ketch and exp©¥a©¥n the F V characteristics of a m etallic conductor at constant tem perature, a 5 7 . S tate O hm ' s Law . d]¨¤erence (p, d. ) ¡¤ 5 6 . U se energy consldera©¥©¥ons to distinguish between e©¥ectrom otlve lorce (e, m , r. ) and potential 5 5 . S tate the dellnltion of electrom otive force. 5 4 , State the dellnlt©¥on b r potentla©¥ dl¨¤erence be©¥ween Iwo pointa. 5 3 . State the equat©¥on re©¥allng current and dr¨¤ voloci©¥y . E xplain all ©¥y nbo©¥©¥ u©¥ed, 5 2 . Stale the equa©¥lon re©¥a©¥ing charge Q and cunen©¥ ©¥. 5 1. E xplain what ©¥©¥ m eant by an e©¥eclrlc current. S e©¥f - c heck Q uestions 1 4 pH Y S ©¥C S D E pA R T M E N T R A F F L E S IN S T ©¥T U T ©¥O N

. , inversely proportional to . N 88/I/13 D inversely proportional to x. C independent ofx. B proportiona©¥ ' to x. Aĉ ¡¤ proportiona©¥ to ©¬. d is . the case and the m eta©¥ tT he resistance betw een H H -«Ò¡¢ tthe diag ram . II m etal rodȘto a depth x as show n in : a cy ©¥ind rical m eta©¥ case Ą conducting liquid fil©¥sP 7 Ą conducting liquid fills 0 0 . 1 0 . 2 0 . 3 0 . 4 0 . Ś(b) W hat is the pow er dissipated at point 1 and point 2 ? V / V 0 . 01(a) W hat is the resistance at point 1 and point 2 7 O . :- l====l P 6 . A n electrical device has the V graph as show n. (resistivity of constantan - 4 . 吕 ¡¿ 1 0 7 Q m ) this wire w ould be needed to m ake a ' 1 2 V , 30 W heater lilam ent? (b) C alculate the resistance per m etre of constantan w ire of diam eter 0 . 35 m m . W hat length of than 5 . 0 V along ©¥ts length. W hat is the m inim um acceptable diam eter of thle cable? (a) A constanten w ire of length 1 5 m is to carry a curreń t of 2 5 A w ith a potent©¥al drop of no m oreP 5 . (b) W nat ©¥s the resistlvlty of the m ateria©¥ from w hich It ls m ade? (a) W nat ls the res©¥stance of thle conductor? current of 4 . 60 A w hen a p . d. o f 60 . 0 V le applied between lte endB . P 4 . A cylindrical conductor w ith a length of 2