In an experiment this circuit is set up. Three ammeters are used to record the currents in the three vertical branches (with
R1 ,
R2 , and
E) . The readings of the ammeters in the resistor branches (i.e. currents in
R1 and
R2 ) are 2 A and 3 A respectively.
Find the equation obtained by applying Kirchhoff’s loop rule in the loop involving
R1 and
R2 .
What will be the reading of the third ammeter (i.e. the branch with
E )? If
E were replaced by 3
E , how would this reading change?
If the original circuit is modified by adding another voltage source (as shown in the following circuit), find the readings of the three ammeters.
In this circuit, assume the currents through
R1 ,
R2 and
R3 are
I1 ,
I2 and
I3 respectively and all are flowing in the clockwise direction.
Find the equation obtained by applying Kirchhoff’s junction rule at point A.
Find the equations obtained by applying Kirchhoff’s loop rule in the upper and lower loops.
Assume
R1 =
R2 = 6 Ω,
R3 = 12 Ω,
r1 =
r2 = 0 Ω,
E1 = 6 V and
E2 = 4 V. Calculate
I1 ,
I2 and
I3 .
For the situation in which
E2 is replaced by a closed switch, repeat parts (a) and (b). Using the values for
R1 ,
R2 ,
R3 ,
r1 and
E1 from part (c) calculate the currents through the three resistors.
For the circuit in part (d) calculate the output power of the voltage source and across all the resistors. Examine if energy is conserved in the circuit.
A student implemented the circuit of part (d) in the lab and measured the current though one of the resistors as 0.19 A. According to the results calculated in part (d) identify the resistor(s). Justify any difference in measured and calculated value.
I
1 + I
3 = I
2
E
1 - I
1 R
1 - I
2 R
2 - I
1 r
1 = 0;
-E
2 + I
1 R
1 - I
3 R
3 - I
3 r
2 = 0
I
1 = 8/15 A,
I
2 = 7/15 A and
I
3 =
- 1/15 A
I
1 = 2/5 A,
I
2 = 3/5 A and
I
3 = 1/5 A
P
E1 = 18/5 W and
P
R1 = 24/25 W,
P
R2 = 54/25 W,
P
R3 = 12/25 W. Yes,
P
E1 =
P
R1 +
P
R2 +
P
R3
Kirchhoff’s rules can be used to analyze any circuit, simple or complex.
Kirchhoff’s first rule—the junction rule: The sum of all currents entering a junction must equal the sum of all currents leaving the junction.
Kirchhoff’s second rule—the loop rule: The algebraic sum of changes in potential around any closed circuit path (loop) must be zero.
The two rules are based, respectively, on the laws of conservation of charge and energy.
When calculating potential and current using Kirchhoff’s rules, a set of conventions must be followed for determining the correct signs of various terms.
The simpler series and parallel rules are special cases of Kirchhoff’s rules.
Conceptual questions
Can all of the currents going into the junction in
[link] be positive? Explain.
Apply the junction rule to junction b in
[link] . Is any new information gained by applying the junction rule at e? (In the figure, each emf is represented by script E.)
(a) What is the potential difference going from point a to point b in
[link] ? (b) What is the potential difference going from c to b? (c) From e to g? (d) From e to d?
Consider the circuit in
[link] , and suppose that the emfs are unknown and the currents are given to be
,
, and
. (a) Could you find the emfs? (b) What is wrong with the assumptions?
(a) No, you would get inconsistent equations to solve.
(b)
. The assumed currents violate the junction rule.
A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?