SECTION A (40 Marks) Compulsory: To be attempted by all candidates.

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1 Question 1 (a) SETION (40 Marks) ompulsory: To be attempted by all candidates. irections: Each question in this part is followed by four possible choices of answers. hoose the correct answer and write it in the space provided. [15] (i) The S.I unit of gravitational force is dyne. newton. gramme force. kilogramme force. nswer: (ii) The electrical energy is converted into sound energy in a microphone. an electric fan. a loud speaker. a washing machine. nswer: (iii) driven gear has 20 teeth. If you want to gain speed, the driving gear should have 25 teeth. 20 teeth. 15 teeth. 10 teeth. nswer:. (iv) ray of light is incident on a glass at an angle of 50. What will be the angle of emergence? nswer: SE/Phy/2015 Page 3 of 20

2 (v) ll of the following physical quantities have unit EXEPT density. upthrust. relative density. apparent weight. nswer: (vi) Pema did an experiment to find the power of lens of focal length 20 cm. The power of the lens was nswer: (vii) student performed an experiment to find the relation between voltage and current. He got the result as shown in the graph given below: Y V The graph represents O I X Newton s law of motion. Faraday s law. Pascal s law. Ohm s law. nswer: (viii) Which of the animals given below use a frequency above 20,000 Hz to catch their prey? bats cats dogs frogs nswer: SE/Phy/2015 Page 4 of 20

3 (ix) Eudon beats a drum in front of a wall which is 500 m away. fter what time does she hear the echo? (Velocity of sound = 340 ms -1 ) 2.95 s 2.94 s 1.36 s 1.37 s nswer: (x) From the following, which one shows the correct relation for resistors in series combination? R R R R R R R R V I R R R R R R R R nswer: (xi) When there is a short circuit, the live and neutral wires must be disconnected by switching off the main switch. single switch. double switch. three-way switch. nswer: (xii) What is the relationship between 1 kilo-calorie and Joule? 1Kcal = 4. 2 J 1 Kcal = 42 J 1 Kcal = 420 J 1 Kcal = 4200 J nswer: SE/Phy/2015 Page 5 of 20

4 (xiii) The heat loss due to convection in a calorimeter can be prevented by covering it with a wooden lid. polishing the outer surface. polishing the inner surface. using a wooden jacket. nswer: (xiv) In an experiment, the surface of the metal plate is heated with a unsen burner. It is observed that an emission takes place. This phenomenon is called field emission. smoke emission. thermionic emission. photoelectric emission. nswer: (xv) The alpha particle is also called a helium nucleus because of the same mass number and atomic number. same mass number but different atomic number. different mass number and atomic number. different mass number but same atomic number. nswer:. (b) Fill in the blanks by writing the suitable word/s. [5] (i) The lens used in a simple microscope is (ii) If the relative density of mercury is 13.6, its density in SI unit will be (iii) Ultraviolet radiation is an example of (iv) The advantage of using high tension wire is to reduce (v) While taking photographs in dim or bright light, must be taken into consideration. SE/Phy/2015 Page 6 of 20

5 (c) Match each item under olumn with the most appropriate item in olumn. Rewrite the correct matching pairs in the space provided. [5] olumn 1. M. of lass II is greater than 1 2. Narrow stem of hydrometer 3. Periodic vibration of decreasing amplitude 4. Work done is negative 5. Maximum wavelength olumn i) damped vibration ii) F d os 180 iii) red light iv) E. L. v) increases sensitivity vi) second harmonic vii) violet light (d) orrect and rewrite the following statements by changing only the underlined words. [5] (i) The intensity of light entering our eyes is controlled by the iris. (ii) The image formed by a concave lens is always real. (iii) When white light passes through a prism it absorbs the white light. (iv) The energy released by a heater which draws a current of 3 at 220 V for 5 minutes is 330 J. SE/Phy/2015 Page 7 of 20

6 (v) To increase the voltage of an alternating current, the primary coil must have more turns than the secondary coils. (e) nswer the following questions: (i) echen observed an inverted image of a tree on the road on a hot sunny day while driving his olero. 1. What property of light is responsible for this phenomenon? [½] 2. Name the phenomenon observed. [½] (ii) Name the part of a transformer that prevents the formation of eddy currents. [1] (iii) uring the construction of buildings, the engineer advises the masons to make base broad. Why does he do so? Give two reasons. [2] (iv) What is resistance? [1] SE/Phy/2015 Page 8 of 20

7 (v) How much heat is required to melt 2 kg of ice? (Specific latent heat of ice = 336 Jg -1 ) [2] (vi) The diagram below shows four test tubes filled with water to different heights. When a vibrating tuning fork is placed over the mouth of the test-tubes, sounds are heard. Which test-tube, or, produces a low frequency sound? Why? [1] (vii) X-rays are useful as well as harmful to human beings. o you agree? Support your answer with one reason. [2] SE/Phy/2015 Page 9 of 20

8 SETION (40 Marks) ttempt any four questions. Question 2 (a) (i) What do you understand by mechanical energy? [1] (ii) What is the advantage of using an inclined plane? [1] (b) (i) How much acceleration will be produced in a body of mass 5 kg acted upon by a force of 1kgf? (g = 9.8 m -2 ) [2] (ii) The same force acting on different bodies will produce different accelerations. Why? SE/Phy/2015 Page 10 of 20 [1]

9 (c) (i) raw a ray diagram to show the use of a convex lens in cinema. [2] (ii) Write any two characteristics of the image formed in (i) above. [1] (d) Write one use of each of the following: [2] (i) SONR (ii) RR Question 3 (a) body weighs 200gf in air and 150gf when completely immersed in kerosene. Find the: 1. volume of the body. [1] 2. upthrust on the body. [1] SE/Phy/2015 Page 11 of 20

10 (b) Give reasons for the following: (i) Prem does not feel the weight of the atmospheric pressure. [1] (ii) nail has a sharp pointed tip. [1] (c) raw the diagram to show the transverse and longitudinal waves. Give one example each. [2] (d) If given the choice, would you like to live in a place with lakes and ponds and where the weather is snowy? Give reasons to support your answer. [2] SE/Phy/2015 Page 12 of 20

11 (e) current I ampere flows through a conductor of resistance R ohm for t second 2 V when the potential difference across it ends is V volt. educe the relation P. [2] t Question 4 (a) efine the following: (b) (i) weight (ii) work Is the mixing of coloured pigments different from the mixing of coloured light? Explain your answer with an example each. [2] SE/Phy/2015 Page 13 of 20 [2]

12 (c) hot steel of mass 200 g is dropped into 0.5 kg of water at 10. The resulting temperature is 40. alculate the temperature of the steel. (Specific heat capacity of steel = 336 JKg -1 º -1 ) [3] (d) (i) What is electromagnetic induction? [1] (ii) What will happen to the direction of the deflection of a galvanometer, if the [2] N-pole of the magnet is moved 1. towards the coil? 2. away from the coil? SE/Phy/2015 Page 14 of 20

13 Question 5 (a) (i) How does the pressure due to a liquid column vary with the density of a liquid? [1] (ii) Fishes can swim up or go down in the water. Explain the statement. [1] (b) (i) The speed of light in air is m/s. alculate the speed of light in glass. The refractive index of glass is 1.5. [2] (ii) Explain why the position of the eye piece must be adjusted while using a simple microscope? (c) (i) Which radiation, beta or gamma, do you think can travel through a long distance in air? Justify your answer. [2] SE/Phy/2015 Page 15 of 20 [2]

14 (ii) What is background radiation? [1] (d) Write one use of ultraviolet radiation. [1] Question 6 (a) From the figure given below: 30 Ω X 20 Ω 0.2 V 2 V alculate the: (i) total resistance of the circuit. [3] SE/Phy/2015 Page 16 of 20

15 (ii) the resistance of X. (b) Write two characteristics of a good electron emitter. [2] (c) single fixed pulley must be used along with a single movable pulley. Why? [2] (d) (i) Why does the refracted ray bend towards the normal as it travels from a rarer to a denser medium? [2] SE/Phy/2015 Page 17 of 20

16 (ii) What do you understand by total internal reflection? [1] Question 7 (a) What do you understand by [2] (b) (i) electromotive force, (ii) current. washing machine is rated 2000 W, 220 V. If it is connected to 220 V mains, calculate the: [3] (i) current drawn by the washing machine, SE/Phy/2015 Page 18 of 20

17 (ii) energy consumed in a day, (iii) cost of energy consumed in a day at the rate of Nu. 1.5 per Kwh. (c) (i) Explain the following: [2] 1. urns caused by steam is more severe than boiling water. 2. Water is used as a coolant in motor car radiators. (ii) efine specific heat capacity. [1] SE/Phy/2015 Page 19 of 20

18 (d) Give reason for the following: [2] (i) soft iron ore is placed at the center of the coil in a galvanometer. (ii) The electron is deflected towards the positive plate in a hot cathode ray tube. SE/Phy/2015 Page 20 of 20

READ THE FOLLOWING DIRECTIONS CAREFULLY:

Alternative No: Index No: 0 1 0 0 8 Supervising Examiner's/Invigilator's initial: Paper 1 (Physics) Writing Time: 1 2 1 Hours Total Marks : 80 READ THE FOLLOWING DIRECTIONS CAREFULLY: 1. Do not write for