PHY102

1. The following are true about electric field lines except that they ______

2. The electric flux is a --------------------------- quantity.

3. What is the self - inductance of an air-core solenoid, 1m long and 0.05m in diameter, if it has 1400 turns?

4.  A potentiometer wire of length 100cm has a resistance of 10$Omega$. It is connected in series to to a resistance R and a cell of emf 2V and negligible internal resistance. A source of emf of 10mV is balanced by a length of 40cm of the potentiometer wire. What is the value of the resistance R?

5. For capacitors in parallel, the potential difference across each capacitor is ---------------------------

6. Find the force on a charge 2C in a field 1Vm^-1---------------------------

7. The magnetic North is found by suspending a bar magnet freely on the --------------------------- axis.

8. The --------------------------- number is the total number of neutrons and protons.

9.  An ammeter is suspected of giving inaccurate readings. In order to confirm the readings, the ammeter is connected to a silver votltameter in series and a steady current is passed for one hour. The ammeter reads 0.56A and 2.0124g of silver is deposited. What is the error is the ammeter reading?

10. A proton is accelerated through a potential difference of 100V and the enters a region in which it is moving perpendicular to a magnetic field of flux density 0.20 T. Find the radius of the circular path in which it will travel.

11. The force between electric charges is known as ---------------------------

12. The energy stored in a system of charges is known as electrostatic potential ---------------------------

13.  The magnetic flux through each loop of a 35-loop coil is given by $(3.6t-0.71t^{3})times10^{-2}Tm^{2}$, where the time is in seconds. Determine the induced emf at t=5.0s.

14. The magnitude of the forces between charged spheres was first investigated by Charles ---------------------------

15. The study of static charges is called ---------------------------

16. The force applied to a conductor is 10N if the charge in the conductor is 5C, what is the electric field intensity?

17. For how long must a steady current of 2A flow through a copper voltameter to deposit $10^{-3}$kg of copper? Z for coper is 0.000329g/C

18.  In the circuit shown, each of the cells has an emf of 2V and internal resistance of $0.1Omega$. Find the current in through the $0.5Omega$

19. The direction of the electric field is opposite to that of the force if the charge is ---------------------------

20.  A magnetic field does not exert a force on a _________

21. The --------------------------- is the SI Unit of electric charge

22. Gaussian surface is an imaginary closed ---------------------------

23. <p style="text-align:left">Six equal point charges Q = 10nC are located at 2,3, 4,5,6,7m. Find the potential at origin.

24.  An electron enters a uniform magnetic field 0.20 T at an angle of $30^{o}$ the field. Determine the pitch of the helical path assuming its speed is $3times10^{7}$ m/s

25. In the cathode ray oscilloscope, when fast moving electrons strike the glass screen coated with zinc and sulphide they cause ---------------------------.

26. The force that is responsible for holding electrons to nuclei to form atoms is called the --------------------------- force

27. The surface integral of the electric field E over a surface is defined to be electric ---------------------------

28. As charge increases, electric flux density ­---------------------------

29. Neutral objects constitute of equal ---------------------------

30.  An air-cored transformer is assumed to be 100% efficient. The ratio of the secondary turns to the primary turns is 1:20. A 240V ac supply is connected to the primary coil and a $6Omega$ load is connected to the secondary coil. what is the current in the primary coil?

31. When a dielectric material is inserted between the plates of a capacitor it increases its ---------------------------

32. Electric flux density is a function of ---------------------------

33.  A single turn coil of cross-sectional area $7.2cm^2$ is in the a magnetic field of flux desity 0.45T. The field which is perpendicular to the coil, is steadily reduced to 0.0T in 5s. Calculate the induced emf.

34. A negative charge ---------------------------negative charge

35. The variation of the compass from the north-south direction is called the ---------------------------

36.  From Gauss’ law which of the following is NOT correct?

37. The principle that electric forces add vectorially is known as the principle of ---------------------------

38. Whose law is employed in electrostatics ­­?

39.  Two charges $Q_{1} = 500mu{C}$ and $Q_{2} = 100mu{C}$ are located on the XY plane at the positions $r_{1} = 3vec{j} m and r_{2} = 4vec{i}$ m. Find the force exerted on the $Q_{2}$

40.  In the space surrounding a wire carrying a steady current, there exists ________

41.  A conductor 2cm long carrying a current of 8A lies at right angles to a magnetic field of which the flux density is 1.0T. Calculate the force exerted on the conductor

42.  An electric field of 50 kV/m is perpendicular to a magnetic field 0.25 T. What is the velocity of a charge whose initial of motion is perpendicular to both fields and which passes through the fields undeflected?

43.  Find the current in through the $0.3Omega$ in the circuit shown

44. When an atom is in the ground state it is said to be ---------------------------

45.  Kirchhof's loop rule is statement of conservation of __________

46. Electric field is measured in Newton per ---------------------------.

47. Electric charge between two bodies can be produced by ---------------------------

48. 1eV is the energy acquired by an electron in falling freely through --------------------------- 1volt.

49. According to Faraday's law, the magnitude of the induced e.m.f is proportional to the rate of change of --------------------------- linking the circuit.

50. According to ohm's law the potential difference is proportional to the ---------------------------