What is the resistance through resistor R given that the current through the circuit is 1 A?

Which of these statements is false?

1. In the case of parallel resistors, the greatest current flow will occur across the  highest resistor.
2. In the case of parallel resistors, the greatest current flow will occur across the lowest resistor.
3. In the case of series resistors, the current flow is the same through each resistor.
4. In the case of series resistors, the voltage drop is greatest across the highest resistor.
5. All are false.

During the cold winter months, some gloves have the ability to provide extra warmth due to an internal heating source. A simplified circuit, similar to those in electric gloves, is comprised of a 9 V battery with no internal resistance and three resistors as shown in the image below. 

What happens to the energy that is dissipated by the resistors?

During the cold winter months, some gloves have the ability to provide extra warmth due to an internal heating source. A simplified circuit, similar to those in electric gloves, is comprised of a 9 V battery with no internal resistance and three resistors as shown in the image below. 

What is the total resistance of the two resistors in parallel (R_A and R₄)?

During the cold winter months, some gloves have the ability to provide extra warmth due to an internal heating source. A simplified circuit, similar to those in electric gloves, is comprised of a 9 V battery with no internal resistance and three resistors as shown in the image below. 

What would happen to the equivalent resistance if R₁ were in parallel with R_A and R₄, instead of in series?

Use the following information to answer questions 1-6:

The circulatory system of humans is a closed system consisting of a pump that moves blood throughout the body through arteries, capillaries, and veins. The capillaries are small and thin, allowing blood to easily perfuse the organ systems. Being a closed system, we can model the human circulatory system like an electrical circuit, making modifications for the use of a fluid rather than electrons. The heart acts as the primary force for movement of the fluid, the fluid moves through arteries and veins, and resistance to blood flow occurs depending on perfusion rates.

To model the behavior of fluids in the circulatory system, we can modify Ohm’s law of V = IR to ∆P = FR where ∆P is the change in pressure (mmHg), F is the rate of flow (ml/min), and R is resistance to flow (mm Hg/ml/min). Resistance to fluid flow in a tube is described by Poiseuille’s law: R = 8hl/πr⁴ where l is the length of the tube, h is the viscosity of the fluid, and r is the radius of the tube. Viscosity of blood is higher than water due to the presence of blood cells such as erythrocytes, leukocytes, and thrombocytes.

The above equations hold true for smooth, laminar flow. Deviations occur, however, when turbulent flow is present. Turbulent flow can be described as nonlinear or tumultuous, with whirling, glugging or otherwise unpredictable flow rates. Turbulence can occur when the anatomy of the tube deviates, for example during sharp bends or compressions. We can also get turbulent flow when the velocity exceeds critical velocity v_c, defined below.

 v_c = N_Rh/ρD

N_R is Reynold’s constant, h is the viscosity of the fluid, ρ is the density of the fluid, and D is the diameter of the tube. The density of blood is measured to be 1060 kg/m³.

Another key feature of the circulatory system is that it is set up such that the organ systems act in parallel rather than in series. This allows the body to modify how much blood is flowing to each organ system, which would not be possible under a serial construction. This setup is represented in Figure 1.

Assume that in Figure 1 R1 = 1/2 mmHg/ml/min, R2 = 2 mmHg/ml/min, R3 = 4 mmHg/ml/min, and R4 = 4 mmHg/ml/min.

The pressure generated by the left ventricle is 100mmHg and the pressure generated from the right ventricle is 50mmHg. What is the rate of flow across R3?

Use the following information to answer questions 1-6:

The circulatory system of humans is a closed system consisting of a pump that moves blood throughout the body through arteries, capillaries, and veins. The capillaries are small and thin, allowing blood to easily perfuse the organ systems. Being a closed system, we can model the human circulatory system like an electrical circuit, making modifications for the use of a fluid rather than electrons. The heart acts as the primary force for movement of the fluid, the fluid moves through arteries and veins, and resistance to blood flow occurs depending on perfusion rates.

To model the behavior of fluids in the circulatory system, we can modify Ohm’s law of V = IR to ∆P = FR where ∆P is the change in pressure (mmHg), F is the rate of flow (ml/min), and R is resistance to flow (mm Hg/ml/min). Resistance to fluid flow in a tube is described by Poiseuille’s law: R = 8hl/πr⁴ where l is the length of the tube, h is the viscosity of the fluid, and r is the radius of the tube. Viscosity of blood is higher than water due to the presence of blood cells such as erythrocytes, leukocytes, and thrombocytes.

The above equations hold true for smooth, laminar flow. Deviations occur, however, when turbulent flow is present. Turbulent flow can be described as nonlinear or tumultuous, with whirling, glugging or otherwise unpredictable flow rates. Turbulence can occur when the anatomy of the tube deviates, for example during sharp bends or compressions. We can also get turbulent flow when the velocity exceeds critical velocity v_c, defined below.

 v_c = N_Rh/ρD

N_R is Reynold’s constant, h is the viscosity of the fluid, ρ is the density of the fluid, and D is the diameter of the tube. The density of blood is measured to be 1060 kg/m³.

Another key feature of the circulatory system is that it is set up such that the organ systems act in parallel rather than in series. This allows the body to modify how much blood is flowing to each organ system, which would not be possible under a serial construction. This setup is represented in Figure 1.

Due to the parallel circuit, the circulatory system has the ability to modify the flow of blood to different organs in the body. The body does this by dilating or constricting vessels to change resistance, and thus the flow of blood.

Assume that, in the diagram in Figure 1, all of the resistances are initially equal. In order to direct more blood flow through R3, the body reduces the resistance to R3 by dilating vessels, and increases R1 and R2 equally by restricting vessels. Assume R_b is the resistance to blood flow through the body from the left ventricle, and it remains constant. What is the value of R3 in terms of R_b?

If each resistor in the diagram above has resistance , determine the equivalent resistance of the circuit.

Given the three resistors below, find the approximate ratio of the equivalent reistance for these resistors in series to their equivalent resistance in parallel.

During the cold winter months, some gloves have the ability to provide extra warmth due to an internal heating source. A simplified circuit, similar to those in electric gloves, is comprised of a 9V battery with no internal resistance and three resistors as shown in the image below. 

What is the net resistance of the circuit?