Chapter 7, Problem 7.4P

When current is flowing through the coil, the direction of the torque can be thought of in two ways. Either as the result of the forces on current carrying wires, or as a magnetic dipole moment trying to line up with an external field (e.g. like a compass). Note: the magnetic moment of a coil points in the direction of the coil's magnetic field at the center of the coil. d) Forces: We can consider the left-most piece of the loop (labeled ○) as a short segment of straight wire carrying current directly out of the page at us. Similarly, we can consider the right-most piece of the loop (labeled ) as a short segment straight wire carrying current directly into the page, away from us. Add to the picture below the two forces due to the external magnetic field acting on these two segments. Then describe how these two forces give a torque and determine if the torque acts to rotate the loop clockwise or counterclockwise according to this picture? B

In each of the following, solve the problem stated. Express your answers in three significant figures. No unit is considered incorrect. 1. For the circuit shown, determine all the currents in each branch using Kirchhoff's Laws. (3 points) 6 5V 2 B C 4 A www 6 VT ww T10 V F E 2. Compute for the total power dissipation of the circuit in previous item. (1 point) 3. Use Maxwell's Mesh to find Ix and VAB for the circuit shown. (3 points) Ix 50 V 20 ww 21x B 4. Calculate all the currents in each branch using Maxwell's Mesh for the circuit shown. (3 points) www 5ი 10 24V 2A 2002 36V

If the mass of substance (1 kg), initial temperature (125˚C), the final temperature (175˚C) and the total volume of a closed container (1 m3) remains constant in two experiments, but one experiment is done with water ( ) and the other is done with nitrogen ( ). What is the difference in the change in pressure between water and nitrogen?

Using the simplified energy balance in Equation 1, suppose there is heat transfer of 40.00 J to a system, while the system does 10.00 J of work. Later, there is heat transfer of 25.00 J out of the system while 4.00 J of work is done on the system. What is the net change in internal energy of the system?

You pour a litre (1 kg) of 25.0˚C water into a 0.500 kg aluminium pan off the stove, but has previously been heated so it starts with a temperature of 120˚C. What is the temperature when the water and the pan reach thermal equilibrium (i.e., what is the temperature of both objects when they reach the same temperature)? Assume that the pan is placed on an insulated pad and a negligible amount of water boils off.

A golf club hits a golf ball and the golf ball’s flight reaches a maximum height of 5.48 m. Calculate the momentum of the golf ball at the maximum height if the mass of the golf ball is 0.459 kg.

• Superposition Theorem • Thevenin's and Norton's Theorem 1. Find the unknown voltage V₁, unknown resistances R1 and R2, and currents flowing through R1 and R2 for the circuit shown below using Superposition Theorem. 40 V + R₁₂ w B C ♥16A 10A www 4A F ww 2 E Ꭰ 2. Use Thevenin's Theorem to find the current flowing in 3-ohm resistor and its power dissipation from the circuit shown in the right. + 3. Use Norton's Theorem for the same instruction as for No. 2. 8 V A www 202 B wwww 20 Ω 10 V + 302 202 www C - 12 V 502 www.

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A rock is dropped from a height of 2.00 m.  Determine the velocity of the rock just before it hits the ground. If the momentum of the rock just before hitting the ground is 14.0 kg m/s, what is the mass of the rock? Is the collision between the rock and the ground elastic or inelastic? Explain.