PHYSICS MC 17 P 1 23
MC 17 P 1 Section I (40 marks) (ll questions are compulsory) Question 1 (a) i) On what factor does the position of the centre of gravity of a body depend? ii) What is the S.I.unit of the moment of force? (b) Name the factors affecting the turning effect of a body. (c) The diagram below shows the surface of a lamina. Redraw the diagram and locate the position of the centre of gravity of the lamina and label it. 60 60 60 (d) Which of the radioactive radiations : i) Cause severe genetical disorder ii) Deflected by an electric field (e) type of single pulley is used to lift a load even though it does not multiply the displacement of effort. i) Name the type of pulley used. ii) For what purpose is such a pulley used? Question 2 (a) i) State the energy coversion during nuclear power generation. ii) State one important precaution required during the disposal of nuclear waste. (b) Redraw the diagram given below and complete the path of the ray till it emerges out of the rectangular glass block PQRS. P Q R (c) Which kind of lever found in the human body is being used by a boy : i) When he holds a load on the palm of his hand. ii) When he raises the weight of his body on his toes. (d) The diagram below shows the optical plane of a lens having same curvature on either side. State with a reason whether f 1 = f 2. S 24 MC 17 P 1
MT EDUCRE LTD. X - ICSE (Physics) Optical plane water air f 1 f 2 (e) i) How is the refractive index of a medium related to its real depth and apparent depth? ii) Which phenomenon of light is reponsible for the blue colour of the sky during the day? Question 3 (a) bucket kept under a running tap is getting filled with water. person sitting at a distance is able to get an idea about the level filled in the bucket without looking at it. i) What characteristic property of sound enables the person to identify this? ii) State the measurable quantity associated with this characteristic of sound. (b) Why is the loud sound heard during acoustic resonance? (c) If the total resistance across is 5, then calculate the value of the resistance X. (d) X You have been provided with a solenoid. - - i) State the polarity at end. ii) Give one advantage of an electromagnet over a permanent magnet. (e) i) Name the device used to protect the electric circuits from overloading and short circuits. ii) What effect of electricity does the above device work? Question 4 (a) i) What is the principle on which a D.C. motor works? ii) Name one device in which such a motor is used. (b) Differentiate between Thermal Capacity and Specific Latent Heat. (c) hot solid of mass 80 g at 100 C is placed in 160 g of water at 20 C. The final steady temperature is 25 C. Calculate the specific heat capacity of the solid. [Specific heat capacity of water = 4200J Cg -1 ] (d) Give two difference between the radioactive decay and nuclear fission. (e) State two sources of backround radiations. + MC 17 P 1 25
X - ICSE (Physics) MT EDUCRE LTD. Section II - ttempt any 4 (40 marks) Question 5 (a) The diagram below shows the moon revolving around the earth. The attractive force exerted by the earth on the moon is and the attractive force exerted by the moon on the earth is. Earth (b) (c) i) State which of the above mentioned forces is a centripetal force. ii) Redraw the diagram and show the direction of force. iii) is the Centrifugal force. State whether this statement is True or False. State where the following statements are true or false. (a) The velocity ratio of a single fixed pulley is always more than (b) The velocity ratio of a single movable pulley is always 2. (c) The velocity ratio of a combination of n movable pulley with fixed pulley is always 2? (d) The velocity ratio of a block and trackle system is always equal to the number of stands of the tackle supporting the load. coolie is pushing a box weighing 1560N up an inclined plane 6.5 m long on to platform, 2.5 above the ground. i) Calculate the mechanical advantage of the inclined plane. ii) Calculate the effort required by the coolie. iii) ctually, if the work done is 10,075J, then calculate the energy wasted. moon Question 6 (a) The diagram below shows a glass prism with critical angle 42. Redraw the diagram and complete the path of the ray, till it emerges out of the prism. Glass prism 48 (b) (c) Name the radiations used: i) in common surgeries to sterilize the tools used in an operation theatre. ii) in burning cancerous cell at the advance stage. iii) whose wavelength lies between 0.01 nm to 10nm. lens is used as a reading glass. i) Name the lens used. ii) Draw a ray diagram to support your answer. iii) Draw one more ray in the same diagram, with a pen to show the effect on the magnification when the object is moved closer to the lens. Question 7 (a) The diagram below shows a sound wave propagating in a solid. displacement (m) 2-2 1.5 3 4.5 6 7.5 distance (m) 26 MC 17 P 1
MT EDUCRE LTD. X - ICSE (Physics) Redraw this diagram and on the same diagram draw another wave of double pitch and having half loudness. (b) i) Define resonance. ii) Two wires and of the same length are stretched equally over two sonometers. Wire resonates with tuning fork of frequently 280Hz and wire resonates with a tuning fork of frequency 480 Hz. State, with a reason, which wire is thicker? (c) wheel of diameter 28 cm is fixed on a vertical wall, can rotate about its centre O. Two weights 40 N and 25 N are suspended from points and on the cirumference which keeps the wheel in equilibrium. Calculate the distance a, as shown in the diagram. 8 cm a O F 2 =25 N F 1 =40 N Question 8 (a) i) Why does the atmosphere become suddenly colder after a hailstorm? ii) Define, Specific latent heat of fusion. (b) i) Two substances and have specifc heat capacities 0.35 J g -10 C 1 and 2.3 J g -10 C 1. One of them is a metal and the other is a non-metal. State, with a reason, which one is a metal : or? ii) When a substance present at melting point, melts, then what is the change in the energy of the molecules of the substance? (c) calorimeter of thermal capacity 63 JK 1 contains 200 g of water present at 70 C. What mass of ice added will bring down the temperature of water to 20 C.? [specific heat capacity of water = 4200 J kg 1 K 1, specific Latent heat of ice = 336000 J Kg 1 ] Question 9 (a) The diagram below shows a light circuit connected using dual control switches. and are two locations. person switches on the bulb at location and goes to location and switches it off. L N i) Identify and state the major mistake in the wiring. ii) Redraw the diagram showing the OFF position of the bulb when the person reaches location. MC 17 P 1 27
X - ICSE (Physics) MT EDUCRE LTD. (b) State the function of the following in the electric circuit : i) Earth wire. ii) M.C.. iii) Kilowatt hour meter. (c) In the circuit diagram given, calculate: i) The current drawn from the cell. ii) The energy consumed in 5 minutes in 6 resistance. 4 3 5 6 4V 0.2 Question 10 (a) The diagram below shows an electrical device used to change voltage. i) Name the device C ii) Name the parts, and C. iii) Why is thicker than? Input C supply Load (b) radioactive source emits three types of radiations, (a) Which radiation has zero mass. (b) Name the radiation which has the lowest ionising power. (c) Name the radiation which has the lowest penetrating power. (d) Give the charge and mass of particles composing the radiations in part (c). (e) When the particle referred to in part (c) becomes neutral, they are found to be the atoms of a rare gas. Name this rare gas and draw a model of its neutral atom. (f) From which part of the atom do these radiations come? (c) i) Identify the nuclear radiation passing through the magnetic field. Magnetic field being acting perpendicularly into the paper as shown in the diagram. x x x x x x ii) Complete the following reactions. () 70 66 25 X + Y 23 () 22 X + 0 e 10-1 x x x Radiation 28 MC 17 P 1