1. [lpt] toil? Which of the following statements are true? Select all cor rect. If none correct, enter N. A) If a current is pointing towards you, the magnetic eld would form a counterclockwise circle. B) The magnetic eld from a current carrying wire follows a circle around the wire. C) If a loop of wire is placed on a table and the current travels clockwise, the magnetic eld points out of the table. D) For an innitely long wire, the magnetic eld gets weaker following a 1/3. dependence. E) If two parallel wires have a current in the same direction, there will be an attractive force between them. 2. [1pt] too Assume that the magnetic eld 5.75m away from an in- nite, straight, currentcarrying wire has an absolute strength of 309 ,uT. Find the current passing through the wire. 3. [lpt] and? A lightning bolt can be approximated as a long straight line of current. Assume that 10.70 of charge pass by a point along the bolt in a time of 1.23 ms. Calculate the magnetic eld at a distance :1: = 1.15 m from the bolt. 4. [1pt] * A solenoid of length L = 60 cm with 1030 turns is connected in series with a resistor, R = 560. A battery supplies the circuit with a potential difference & = 107 V. Calculate the magnetic field inside the solenoid. L 100000000000 R WW 3 5. [1pt] Aww Consider a 1.55m long wire solenoid with 50 turns. Calcu- late the absolute magnetic field strength inside the solenoid when it is carrying a 13.4 A current.000000000000 IY 6. [1pt] * * * Consider two infinite wires, one of which has been bent into a rectangular I1 U-shape of width L = 148mm, as shown. The bottom of the U is a L distance d = 26mm from the second wire. Calculate the force exerted by the straight wire on the U-shaped d wire, assuming that I1 = 7.20 A and I2 = 6.20 A. 12 Hint: Draw the force on each segment of the upper wire individually before you do any calculations Faraday's Law and Lenz's Law 7. [1pt] Aux Which of the following statements are true? Select all cor- rect. If none correct, enter N. A) When a current is produced by a changing magnetic field, the current will act to increase the change. B) Suppose a loop is on the table. If the magnetic field points away from the table and gets smaller, the current in the loop will flow counterclockwise. C) The Electromotive Force (EMF) in a loop depends on the time derivative of the magnetic flux through the loop. D) If there is a changing magnetic flux through a loop, we will measure a current. E) The magnetic flux through a loop depends on the area of the loop, the strength of the magnetic field, and the angle between them.11. [1pt] *Aw A circular loop of radius r = 5 cm is located in the plane of the page in- X side a homogeneous magnetic field X X of B = 0.5 T pointing into the page. The loop has resistance of 5m0. X X The magnetic field is steadily de- creased to OT in 0.2s. Determine X X B the induced current in the loop and its direction. Enter your numerical answer. 12. [1pt] Aww Enter the direction as either 'cw' or 'ccw'. Note, you only have 1 try! 13. [1pt] * * * The graph shows the magnetic flux through a square coil of wire with 86 turns as a function of time. The coil is rotating with constant angular velocity in a uniform 3.10 T magnetic field. Calculate the magnitude of the induced emf at time t = 1.51s. 2 P (10 Wb) 0 - 1 -2 0 1 2 3 4 5 6 t (s)8. [1pt] Aww A circular wire loop of radius B R = 30 cm is immersed in a uni- form magnetic field B = 7.39 T. R The loop is inclined at angle 0 = 430 with respect to the B- field. Calculate the magnetic flux through the loop. A rectangular wire loop is moving with speed v into a re- gion of uniform magnetic field B = 455 mT, as shown, where L = 34 cm. L R 9. [1pt] * * Find v so that an emf of 2.0 V is induced. 10. [1pt] Aww What is the induced current if R = 12 0