A 10-turn square coil of area 0.036 m2 and a 6-turn circular coil are both placed at an angle of 25 to the same changing magnetic field. The voltage induced in each of the coils is the same. What is the area of the circular coil?
a. 0.072 m2
c. 0.072 m2
b. 0.060 m2
d. 0.60 m2
[Ques. 2] A tire stops a car by use of friction. What modulus should we use to calculate the stress and strain on the tire?
a. Young's modulus
c. shear modulus
b. compression modulus
d. bulk modulus
[Ques. 3] A square coil, enclosing an area with sides 3.0 cm long, is wrapped with 2500 turns of wire. A uniform magnetic field perpendicular to its plane is turned on and increases to 0.12 T during an interval of 1.0 s. What average voltage is induced in the coil?
a. 2.5 V
c. 1.2 V
b. 0.27 V
d. 0.12 V
[Ques. 4] Consider two steel rods, A and B. B has three times the area and twice the length of A, so Young's modulus for B will be what factor times Young's modulus for A?
a. 3.0
c. 1.5
b. 0.5
d. 1.0
[Ques. 5] A long wire along the x axis is carrying a current increasing at a constant rate in the +x direction. A rectangular coil lies in the x-y plane in the 4th quadrant. In which direction is the induced magnetic field at the center of the rectangular coil?
a. in the z direction
b. There is no direction; the induced current in the coil is zero since the x axis and the coil are in the same plane.
c. in the +z direction
d. No direction can be found since the orientation of the rectangular coil is not given.
[Ques. 6] Bar One has a Young's modulus that is bigger than that of Bar Two. This indicates Bar One:
a. is longer than Bar Two.
b. has a greater cross-sectional area than Bar Two.
c. has a greater elastic limit than Bar Two.
d. is made of material that is different from Bar Two.
[Ques. 7] If the induced current in a wire loop were such that the flux it produces is in the same direction as the change in external flux causing the current, which of the following conservation laws would end up being violated?
a. energy
c. momentum
b. charge
d. angular momentum
[Ques. 8] A uniform pressure of 21 105 N/m2 is applied to all six sides of a copper cube. What is the percentage change in volume of the cube? (for copper, B = 14 1010 N/m2)
a. 2.4 10-2
c. 8.4 10-2
b. 1.5 10-3
d. 0.5 10-3
[Ques. 9] If a bar magnet is falling through a loop of wire, the induced current in the loop of wire sets up a field which exerts a force on the magnet. This force between the magnet and the loop will be repulsive when:
a. the magnet enters the loop.
c. never.
b. the magnet is leaving the loop.
d. the magnet is halfway through.
[Ques. 10] The bulk modulus of a material, as a meaningful physical property, is applicable to which of the following?
a. only solids
c. only gases
b. only liquids
d. solids, liquids and gases
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