Description : The potential difference of a cell in an open circuit is 6 V, which falls to 4 V when a current of 2 A is drawn from the cell. Calculate the emf and t
Last Answer : The potential difference of a cell in an open circuit is 6 V, which falls to 4 V when a ... Calculate the emf and the internal resistance of the cell.
Description : A potential difference of V = 100 ± 2 volt, when applied across a resistance R gives a current of 10 ± 0.5 ampere.
Last Answer : A potential difference of V = 100 2 volt, when applied across a resistance R gives a current of 10 ... percentage error in R given by R = V/I.
Description : Current in a circuit if resistance of 15 Ω and potential difference of 3.0 V is applied across it's ends is A. 1 A B. 2 A C. 0.5 A D. 0.20 A
Last Answer : 0.20 A
Description : The potential differnce between the terminals of a battery of emf 6.0 V and internal resistance `1 Omega` drops to 5.8 V when connected across an exte
Last Answer : The potential differnce between the terminals of a battery of emf 6.0 V and internal resistance ... resistor . Find the resistance of the external res
Description : A cell which has an emf `1.5` V is connectedin series with an external resistance of `10Omega`. If the potential difference across the cell is `1.25`
Last Answer : A cell which has an emf `1.5` V is connectedin series with an external resistance of `10Omega`. If the potential ... `0.25` C. `1.5` D. `0.3`
Description : An electron falls through a potential differsence of `1000 V` and gives up `1.6 xx10^(-16) J` of energy. What is the charge on the electron?
Last Answer : An electron falls through a potential differsence of `1000 V` and gives up `1.6 xx10^(-16) J` of energy. What is the charge on the electron?
Description : An electron falls through a potential difference of `50,000 V`. What is the energy acquired by it?
Last Answer : An electron falls through a potential difference of `50,000 V`. What is the energy acquired by it?
Description : The emf of a cell E is 15 V as shown in the figure with an internal resistance of `0.5Omega`. Then the value of the current drawn from the cell is
Last Answer : The emf of a cell E is 15 V as shown in the figure with an internal resistance of `0.5Omega`. Then the value of ... A. `3A` B. `2A` C. `5A` D. `1A`
Description : Find the potential of V = 60sin θ/r 2 at P(3,60,25) a) 5.774 b) 6.774 c) 7.774 d) 8.774
Last Answer : a) 5.774
Description : An electrical component is connected across a 120 volt 60 hertz AC supply. What is the current drawn by the component if the impedance is 200 ohms? A. 0.01 amperes B. 0.60 amperes C. 1.67 amperes D. 100 amperes
Last Answer : Answer: B
Description : Barrier potential in a P-N junction is caused by (A) Thermally generated electrons and holes. (B) Diffusion of majority carriers across the junction. (C) Migration of minority carriers across the junction. (D) Flow of drift current.
Last Answer : (B) Diffusion of majority carriers across the junction.
Description : Consider the following statements regarding the formation of P-N junctions: 1. Holes diffuse across the junction from P-side to N-side 2. The depletion layer is wiped out. 3. There is continuous flow of current across the junction 4 ... correct? (a) 1 and 3 (b) 2 and 3 (c) 1 and 4 (d) 2 and 4
Last Answer : Ans: (c) When a pn-junction is formed, there will be diffusion of carries across the junctions followed by recombination, and the creation of a depletion layer across which a ... potential is established, which will prevent further diffusion of carries across the junction, leading to equilibrium
Description : In the circuit shown the voltage drop across the `15Omega` resistor is `30 V` having the polarity as indicated. The ratio of potential difference acro
Last Answer : In the circuit shown the voltage drop across the `15Omega` resistor is `30 V` having the ... difference across `5Omega` and resistance `R` is
Description : A potential difference of 10 V is applied across a conductor of resistance `1 k Omega`. Find the number of electrons flowing through the conductor in
Last Answer : A potential difference of 10 V is applied across a conductor of resistance `1 k Omega`. ... of electrons flowing through the conductor in 5 minutes.
Description : The drift speed of electrons in copper wire of diameter and length `l` is `v` . If the potential difference across the wire is doubled, then the new d
Last Answer : The drift speed of electrons in copper wire of diameter and length `l` is `v` . If the potential ... `2upsilon` C. `3upsilon` D. `upsilon//2`
Description : In the circuit diagram shown in figure, potential difference across `3Omega` resistance is 20 V. Then, match the following two columns.
Last Answer : In the circuit diagram shown in figure, potential difference across `3Omega` resistance is 20 V. Then, match the following two columns.
Description : The potential difference across the gap of a spark plug ranges between a) 10-20 mV b) 10-20 V c) 10-20 kV d) 10-20 MV
Last Answer : ans a
Description : The potential difference across a `2 H` inductor as a function of time is shown in figure. At time `t=0`, current is zero Current `t = 2` second is
Last Answer : The potential difference across a `2 H` inductor as a function of time is shown in figure. At time `t=0`, current is ... B. `3 A` C. `4 A` D. `5 A`
Description : A voltmeter of resistance `998 Omega` is connected across a cell of emf 2 V and internal resistance `2 Omega`. Find the p.d. across the voltmeter, tha
Last Answer : A voltmeter of resistance `998 Omega` is connected across a cell of emf 2 V and internal resistance `2 Omega`. Find the ... B. `3.5 V` C. 5 V D. 6 V
Description : What is the maximum current allowed to be drawn from the secondary of a 2 KVA step-down transformer with a turns ratio of four to one if connected across a 440 volt line? A. 1.1 amps B. 4.5 amps C. 18.1 amps D. 22.7 amps
Last Answer : Answer: C
Description : When a current of 0.5 A is passed through two resistances in series, the potential difference between the ends of the series arrangement is 12.5 V. On
Last Answer : When a current of 0.5 A is passed through two resistances in series, the potential difference between ... ends is 6 V. Calculate the two resistances.
Description : Average power dissipated in resistor if sinusoidal p.d of peak value 25 V is connected across a 20 Ω resistor is A. 15.6 W B. 15 W C. 16 W D. 17 W
Last Answer : 15.6 W
Description : The potential drop between the terminals of a battery is equal to the battery's EMF when: w) no current is drawn from the battery x) a very large current is drawn from the battery y) the internal resistance of the battery is very large z) the resistance in the external circuit is small
Last Answer : ANSWER: W -- NO CURRENT IS DRAWN FROM THE BATTERY
Description : Ionisation potential applied across the electrodes of electrostatic tar precipitator is around (A) 230 V AC (B) 60 KV AC (C) 230 V DC (D) 60 KV DC
Last Answer : (D) 60 KV DC
Description : If the potential is given by, V = 10sin θ cosφ/r, find the density at the point P(2, π/2, 0) (in 10 -12 units) a) 13.25 b) 22.13 c) 26.31 d) 31.52
Last Answer : b) 22.13
Description : A voltmeter arranged across the power supply measures A. potential difference B. e.m.f C. current D. resistance
Last Answer : e.m.f
Description : In an experiment on studying the dependence of current flowing through a given resistor on the potential difference applied across it, list two ways how a student would change the values of current in the circuit?
Last Answer : Answer. There are two ways in which a student can change the values of current in the circuit: By increasing or decreasing the number of cells. By changing the value of resistance.
Description : While performing an experiment to study the dependence of current on the potential difference across two ends of the resistor, a student keeps the circuit closed for a long time to measure the current and potential difference. State how the resistance of the resistor will be affected?
Last Answer : Answer. When the circuit is closed for a long time, the flow of current will be in excess which causes unwanted heating in the resistor and changes the value of resistance.
Description : The potential difference across a 4 ohm resistor is 20 volts. What is the current in the resistor?
Last Answer : ANSWER: 5 AMPS
Description : A 1000 watts heater is connected to a 240 V AC Supply. Then the current drawn by the heater is
Last Answer : A 1000 watts heater is connected to a 240 V AC Supply. Then the current drawn by the heater is 4.166 amperes
Description : The current drawn by a 120 - V d.c. motor of armature resistance 0.5 Ω and back e.m.f. 110 V is .......... ampere.
Last Answer : The current drawn by a 120 - V d.c. motor of armature resistance 0.5 Ω and back e.m.f. 110 V is 20 ampere.
Description : The resting membrane potential of a cell a. is dependent on the permeability of the cell membrane to K+ being greater than the permeability to Na+ b. falls to zero immediately when Na+ ... the equilibrium potential for Na+ e. is markedly altered if the extracellular Na+ concentration is increased
Last Answer : is dependent on the permeability of the cell membrane to K+ being greater than the permeability to Na+
Description : Two unpedauces given by Z1 = 10 + j5 and Z2 = 8 + j9 are joined in parallel and connected across a voltage of V = 200 + j0. Calculate the circuit current and branch currents. Draw the vector diagram.
Last Answer : Solution: Given, Z1=10+j5, Z2=8+j9, V=200+j0
Last Answer : Req= (1/1200 +1/560 + 1/2.1)^-1 = 2.1 ohms RT= 2.1 + 7.8 = 9.9 ohms IT = V/R = 24/9.9 = 2.4 A Veq= R I = 2.1 2 ... 7.8 = 12.096 w = 44.928 w _________________________________________ By: Ellis-Junior Kamatjipose [email protected]
Description : If E is the emf of a cell of internal resistance r and external resistance R, then potential difference across R is given as
Last Answer : If E is the emf of a cell of internal resistance r and external resistance R, then potential difference across R is given ... /R)` D. `V=E//(1+R//r)`
Description : If S is the potential infiltration, P is rainfall in cm in a drainage of a soil with fair pasture cover, the direct run off Q in cm is given by (A) Q = (P - 0.1 S)²/(P + 0.4 S) (B) Q = (P - 0.2 S)²/(P + 0.6 S) (C) Q = (P - 0.2 S)²/(P + 0.8 S) (D) Q = (P - 0.2 S)²/(P + 0.2 S)
Last Answer : Answer: Option C
Description : A well collimated parallel pencil of cathode rays falls through a potential difference `3kV` & enters the spacing between two parallel metallic plates
Last Answer : A well collimated parallel pencil of cathode rays falls through a potential difference `3kV` & enters the ... Given the length of the plates is 10 cm.
Description : The slope of the graph showing the variation of potential difference V on X-axis and current Y-axis gives conductor
Last Answer : The slope of the graph showing the variation of potential difference V on X-axis and ... resistivity C. reciprocal of resistance D. conductivity
Description : Assertion : Current versus potential difference (i-V) graph for a conductor at two different temperatures `T_(1)` and `T_(2)` is shown in figure. Henc
Last Answer : Assertion : Current versus potential difference (i-V) graph for a conductor at two different ... If Assertion is false but Reason is true.
Description : In the circuit shown in figure switch S is closed at time t=0 Potential difference across `3Omega` resistance at time t is given by
Last Answer : In the circuit shown in figure switch S is closed at time t=0 Potential difference across `3Omega` resistance at time t ... 2t)` D. `18(1-e^(-t//9))`
Description : When the potential difference of 4 volt is applied across resistance, 10J energy is converted. Find the charge flows. a. 0.20 C b. 2.5C c. 5C d. 10C
Last Answer : b. 2.5C
Description : Find the potential of the function V = 60cos θ/r at the point P(3, 60, 25). a) 20 b) 10 c) 30 d) 60
Last Answer : b) 10
Description : The chemical potential of a component (μi) of a phase is the amount by which its capacity for doing all work, barring work of expansion is increased per unit amount of substance added for an infinitesimal addition at constant temperature and ... , nj (C) (∂H/∂ni)S, P, nj (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Two half-reactions of an electrochemical cell are given below : MnO-4 (aq) + 8H+ (aq) + 5e- → Mn2+ (aq) + 4H2O (I), E° = 1.51 V Sn2+ (aq) → Sn4+ (aq) + 2e- ... the redox equation from the standard potential of the cell and predict if the reaction is reactant favoured or product favoured. -Chemistry
Last Answer : The reactions can be represented at anode and at cathode in the following ways : At anode (oxidation) : Sn2+ → = Sn4+ (aq) + 2e- ] 5 E° = + 0.15 V At cathode (reduction) : MnO-4(aq) + 8H+ ... = E°cathode - E°anode = 1.51 - 0.15 = + 1.36 V ∴ Positive value of E°cell favours formation of product.
Description : Two half-reactions of an electrochemical cell are given below : MnO-4 (aq) + 8H+ (aq) + 5e- → Mn2+ (aq) + 4H2O (I), E° = 1.51 V Sn2+ (aq) → Sn4+ (aq) + ... -reactions and calculate the cell potential from the standard potentials and predict if the reaction is reactant or product favoured. -Chemistry
Last Answer : The reactions can be represented at anode and at cathode in the following ways : At anode (oxidation) : Sn2+ → Sn4+ (aq) + 2e- ] 5 E° = + 0.15 V Af cathode (reduction) : MnO-4(aq) + 8H+ ( ... = E°cathode - E°anode = 1.51 - 0.15 = + 1.36 V ∴ Positive value of E°cell favours formation of product.
Description : The potential barrier for germanium is _______ (a) 0.6 V (b) 0.2 V (c) 0.3 V (d) 0.5 V
Last Answer : (c) 0.3 V
Description : The emf of a battery is 4.0 V and its internal resistance is `1.5 Omega`. Its potential difference is measured by a voltmeter of resistance `1000 Omeg
Last Answer : The emf of a battery is 4.0 V and its internal resistance is `1.5 Omega`. Its potential ... percentage error in the reading of emf shown by voltmeter.
Description : The true power indicated by a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the _____________. A. power factor of the load B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load
Last Answer : Answer: A
Description : The true power indicated by the pointer movement of a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the ____________. A. power factor of the ... B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load
Description : Compute the power consumed by a material with current density 15 units in an area of 100 units. The potential measured across the material is 20V. a) 100kJ b) 250kJ c) 30kJ d) 15kJ
Last Answer : c) 30kJ