SS 1 THIRD TERM EXAMINATION PHYSICS

   THIRD TERM                 

Examination malpractices may lead to a repeat of the subject or suspensions don’t be involved.   

SUBJECT   PHYSICS             CLASS: S. S. S 1     DURATION 2HR

SECTION A

INSTRUCTION: Attempt all question in this section.

1. A current of 10A passes through a conductor for 10s, calculate the charge flowing through the conductor (a) 100.0C (b) 10.0C (c) 1.0C (d) 0.1C
2. The symbol               represents (a) resistor (b) capacitor (c) diode (d) current
3. The SI unit of voltage is (a) ampere (b) volts (c) ohm’s (d) coulomb
4. The symbol                (a) resistor (b) capacitor (c) diode (d) current
5. Which of the following correctly express Ohm’s law (a) V=IR (b) Q=It (c) R=IV (d) W=QV
6. A car fuse marked 15A and operates normally on a 12V battery, calculate the resistance of the fuse wire (a) 0.8 Ω (b) 1.3 Ω (c) 3.0 Ω (d) 27.0 Ω 

Use the diagram below to answer question 7

        200Ω

    5V

1. Ω          100 Ω

1. Calculate the potential difference across each of the 100 Ω resistor (a) 1v (b) 2v (c) 4v (d) 5v
2. Five 5Ω resistors are connected in parallel, the equivalent resistance is (a)1Ω (b) 2.5Ω (c) 6.5 Ω (d) 12.5 Ω

1.     P    1Ω      2 Ω

3 Ω        2 Ω

Q    1 Ω      2 Ω

The total resistance measured at PQ in the diagram above is (a) 18.0Ω (b) 11.0Ω (c) 4.0Ω (d) 2.0Ω

1. A wire of 5Ω resistance is drawn out so that its new length is twice the original length. If the resistivity of the wire remains the same and the cross-sectional area is halved, the new resistance is(a) 5Ω (b) 10Ω (c) 40Ω (d)20 Ω
2. Find the heat in joules produced in an electric coil of resistance 15ohms when a current of 5 amperes flows through it for 30 minutes (a) 6.75×105 (b) 0.75×105 (c) 2.5×105 (d) 6.75×102
3. A lamp is rated 240V, 60W, calculate the resistance of its filament (a) 240Ω (b) 360Ω (c) 960Ω (d) 1440Ω
4. A fully-charged 6v accumulator can give a current of 2A for 30hours. Calculate the energy given out during its discharge (a) 1.2×103J (b) 1.3×106J (c) 0.5×103J (d) 2.5×106J
5. If a p.d of 240v is applied across a lamp that supplies energy at the rate of 60w. What is the value of the resistance? (a) 96Ω (b) 48Ω (c) 960Ω (d) 900Ω
6. A wire of length 5m and cross sectional area 4.0×10-8m2 has a resistance of 10Ω. Calculate the conductivity (a) 1.25×107 Ω-1m-1 (b) 2.50×107 Ωm-1 (c) 5.00×107 Ω-1m-1 (d) 8.00×107 Ω-1m-1
7. Given that the diameter of a cylindrical material wire whose 1.0m length has a resistance of 2.0ohms? Calculate the resistivity of the wire (a) (b) (c) (d) 
8. The headlamp of a car takes a current of 0.40A from a 12v supply. Calculate the energy produced in 5 minutes (a) 1.25×103J (b) 0.5×107J (c) 1.4×103 (d) 1.25×10-3
9.  A heating coil marked 1000W is used to heat water for 15 minutes. Calculate the energy given out. (a) 900KJ (b) 90KJ(c) 9000KJ (d) 900000KJ

Use the information below to answer questions 19 and 20

Two torch light batteries each having e.m.f. of 1.5V and an internal resistance of 1ohm are connected to a resistor of 5ohm. Calculate the current in this resistor if the cells are connected in:

1. Series (a) 0.43A (b) 2.1A (c) 0.27A (d) 1.5A
2. Parallel (a) 0.43A (b) 2.1A (c) 0.27A (d) 1.5A 
3. The maximum power dissipated by 100Ω resistor in a circuit is 4W; calculate the voltage across the resistor (a) 10V (b) 20V    (c) 25V (d) 400V
4. Fuse is a protective device, design to ……….. (a) stick (b) melt (c) disappear (d) repel
5. The conductor designed to melt is called ……. (a) fuse element (b) fuse (c) resistor (d) cartridge fuse
6. The following are examples of fuse except ……. fuse (a) re-wire able (b) merger (c) cartridge (d) high breaking capacity
7. Which of the following statements about matter is not correct (a) each molecule of a substance moves to and fro about a fixed position (b) energy is require to break the forces of attraction between molecules (c) molecules of liquids are more closely packed than those of gases (d) molecules of solids move more freely than molecules of liquids
8. A lamp 100W, 250V is lit for 5hours. If it operates normally and 1kwh of electrical energy costs 2naira, what is the cost of lighting the lamp? (a) 1 naira (b) 2 naira (c) 5naira (d) 10 naira
9. An electric iron draws a current of 5.0A when connected to a 250V supply. Calculate the energy consumed by the iron if it is used for 10minutes (a) 750.0KJ (b) 550.0KJ (c) 41.6KJ (d) 20.0KJ
10. A wire of length 200cm and cross-sectional area 2×10-3cm2 has a resistance of 0.20ohm. Calculate its electrical conductivity (a) 2×10-6Ω-1m-1 (b) 5×105Ω-1m-1 (c) 2×106Ω-1m-1 (d) 5×106Ω-1m-1
11. The nucleus of an atom consist of (a) proton and electron (b) neutron and electron (c) proton and neutron (d) none of the above
12. The odour of a leaking gas is perceived at a distance from the source. This is made possible by the process of (a) capillarity (b) evaporation (c) osmosis (d) diffusion
13. When is atom said to be electrically neutral   (a) when the number of proton equals the number of neutron    (b) when the number of protons     equals the number of electrons   (c) when the number of proton is     greater than the number of electron   (d) when the number of neutron     equals the number of electron
14. Atoms of solids having crystalline structures are arranged in regular patterns called (a) energy levels (b) atomic structure (c) lattices (d) orbits
15. Unit cell is also known as (a) monoclinic system (b) polyclinic system (c) space lattice (d) none of the above
16. Crystal structure is generally used to describe (a) the external structure of solids (b) the internal structure of solids (c) the internal structure of liquids   (d) the external structure of liquid
17. In which of the following are crystalline structures observable? I. Gas II. Liquid III. solid (a) I only (b) II only (c) III only (d) I and II
18. ………… substance has a definite internal arrangement of particles (a) Amorphous (b) Crystalline (c) Elastic (d) Atomic
19. A few grains of table salt were put in a cup of cold water kept at constant temperature and left undisturbed. Eventually, all the water tasted salty. This action is due to: (a) osmosis (b) diffusion (c) conductivity (d) capillarity
20. Which of these is the effect of surface tension (a) the floating of the ship in water (b) Soap bubbles are spherical in shape (c) the osmotic pressure of the liquid (c) all of the above
21. Which of the following factors may be used to explain why a steel pin may float in water? (a) the force of cohesion between the pin and the water (b) the force of adhesion between the pin and the water (c) the surface tension of water (d) the force due to capillarity
22. In which of the following is surface tension important? (a) the floating of the ship in water (b) the floating of dry needle in water (c) the floating of a balloon in air (d) the diffusion of sugar solution across a membrane
23. The rise or fall of a liquid in a narrow tube is due to (a) the friction between the walls of the tube and the liquid (b) the viscosity of the liquid (c) the osmotic pressure of the liquid (d) the surface tension of the liquid
24. Young’s modulus of elasticity is the ratio of stress to strain, provided the load does not exceed the (a) breaking point (b) elastic limit (c) yield point (d) stress limit
25. The ratio of tensile stress to tensile strain is known as ….. (a) modulus of rigidity (b) modulus of elasticity (c) Young’s modulus (d) shear modulus
26. The SI unit of tensile stress is ….. (a) N/m (b) Nm (c) N/m2 (d) m2
27. Hooke’s law states that (a) F α A (b)F α e  (c) E α F (d) E α A
28. The spiral spring of a spring balance is 25.0cm long when 5N hangs on it and 30.0cm when the weight is 10N. What is the length of the spring if the weight is 3N assuming Hooke’s law is obeyed? (a) 15.0cm (b) 17.0cm (c) 20.0cm (d) 23.0cm
29. A spring is stretched 40mm by a force of 15N, what is the work done by the force? (a) 3J (b) 0.6J (c) 0.3J (d) 9J
30. A spring of force constant 1500Nm-1 is acted upon by a constant force of 75N. Calculate the potential energy stored in the spring (a) 1.9J (b) 3.2J (c) 3.8J (d) 5.0J
31. A spring 20cm long is stretched to 25cm by a load of 50N, what will be its length when stretched by 100N assuming that the elastic limit is not reached? (a) 30cm (b) 10cm (c) 35cm (d) 40cm
32. The action of water rising up in the stem of a plant is due to (a) surface tension (b) osmosis (c) transpiration (d) capillarity

SECTION B

INSTRUCTION: Attempt any three questions from this section.

1. (a) A battery of four cells each of e.m.f. 1.5V and internal resistance 1.0 Ω is connected in series with a parallel combination of two 2 Ω resistors. Draw the circuit diagram and calculate: (i) the combined external resistance (ii) the current in the circuit (iii) the lost volts in the battery (iv) the current in one of the two resistors                            8marks

(b) State Ohms law                        2marks

1. (a) Determine the length and conductivity of a wire with diameter 2.0mm constructed from an alloy of resistivity 22×10-8Ωm, if its resistance is 0.42Ω
   (π=22/7)                                4marks

(b) Electricity is supplied to Elias international school along a cable of total resistance 0.5Ω with the maximum current drawn from the main as 100A. The maximum energy dissipated as heat for 1hour is?    3marks

(c) Mention 3 factors that affect the resistance of a wire    3marks

1. (a) A landlord has six 30w electric lighting bulb, four 60w bulb and two 200w bulb. If he has all the point on for 10hrs, what is the bill for the month of February 2018?                            8marks

(b) State four factors that affect the rate of diffusion    2marks

1. (a) A battery of 20v and internal resistance 5Ω is connected to a resistor 0f 20Ω. Calculate the value of: (i) electric current (ii) terminal voltage (iii)lost voltage                                6marks

(b) Give two differences between crystalline and amorphous substances 2marks

(c) Give two ways of reducing surface tension        2marks

1. (a) Sketch the graph of the relation between the extension of a spiral spring and the load attached to it when it is gradually loaded up to elastic limit. Indicate the following points: elastic limit, yield point, maximum load, and breaking point.                            5marks

(b) If the spring has a stiffness of 950Nm-1, what work will be done in extending the spring by 60mm?                    3marks

(c) Define surface tension                    2marks