Question

1) An electron traveling horizontally enters a region where a uniform magnetic field is directed into the plane of the paper as shown. Which one of the following phrases most accurately describes the motion of the electron once it has entered the field? electron a) downward and circular b) downward and parabolic c) upward and circular d) upward, along a straight line х x X X X X 2) The magnetic field at the center of a current carrying wire is: a) is one half the field as the surface b) Cannot be known without the current. c) Zero d) The same as at the surface of the wire e) Is equal to the magnetic field at the surface divided by the radius of the wire 3) A long, straight wire carries a current I. If the magnetic field at a distance d from the wire has magnitude B, what is the magnitude of the magnetic field at a distance 3d from the wire? a) B/3 b) 3B c) B/9 d) 9B e) 42B 4) Two wires run from the ceiling to the floor and the distance between them is 10 cm. Wire A carries a current I. Wire B carries a current 21. Which of the following statements are true? a) The force on wire A is 2F, while the force on wire B is F. The force is attractive. b) The force on wire A is F, while the force on wire B is 2F. The force is attractive. c) The force on wire A is 2F, while the force on wire B is F. The force is repulsive. d) The force on wire A is F, while the force on wire B is 2F. The force is repulsive. e) None of the other statements are true. 5) We desire to measure the current through and the voltage across a resistor connected in a circuit. How should an ammeter and a voltmeter be connected to the resistor? a) Both are connected in series with the resistor. b) It depends on the amount of current and voltage to be measured. c) The ammeter is connected in series and the voltmeter is connected in parallel with the resistor. d) Both are connected in parallel with the resistor. e) The ammeter is connected in parallel and the voltmeter is connected in series with the resistor.

Answer 1

1) As we know when a charse particle enter normally in the magnetic field it traces a Circalae path, force downward so Answer a) downward and circulas. 2) magnetic field at centre of cassent cassying wire is zero (c) 3) napretic field due to love wire B= to I 20(30) B₂ = no I 1 25 d B2=B (9) 3 4) None of statement is true as direction of current in wires not given. (e) 5) An ammetel is connected in series with resistor while voltmeter connected in parallel with resis for (c)