Short Answer Typei) Why does a bottle of soft drink cool faster when surrounded by ice cubes than by ice cold water, both at 0o C.
ii) A certain amount of heat Q will warm 1 g of material X by 30o C and 1 g of material Y by 4o C. Which material has a higher specific heat capacity?i) A bottle of soft drink cools faster whne surrounded by ice cubes than by ice cold water because 1 gm of ice at 0o C takes 336 J of heat energy from the drink to melt into water at 0o C. Thus, drink loses an additional 336 J of heat energy for 1 g ice at 0o C than 1 gm ice-cold water at 0o C. Therefore, cooling produced by 1 g ice at 0o C is more than that by 1 gm water at 0o C.
ii) Specific heat capacity 
So, material X has a higher specific heat capacity.
A calorimeter of mass 50 g and specific heat capacity 0.42 J g-1oC-1 contains some mass of water at 20o C. A metal piece of mass 20 g at 100 degree C is dropped into the calorimeter. After stirring, the final temperature of the mixture is found to be 22o C. Find the mass of water used in the calorimeter.
Which of the radioactive radiations:
i) can cause severe genetic disorders?
ii) are deflected by an electric fieldA radioactive nucleus undergoes a series of decays according to the sequence: 
If m is the mass number and atomic number of X3 are 172 and 69 respectively, what is the mass number and atomic number of X?
Name the radiations:
i) Used for photography at night.
ii) Used for detection of fracture in bones.
iii) Whose wavelength range is from 100 
i) What is meant by radioactivity?
ii) What is meant by nuclear waste?
iii) Suggest one effective ways for the safe disposal of nuclear waste.
Long Answer TypeA coolie is pushing in a box weighing 1500 n up an inclined plane 7.5 m long on to a platform 2.5 m above the ground,
i) Calculate the mechanical advantage of the inclined plane.
ii) Calculate the effort applied by the coolie.
iii) In actual practice, the coolie needs to apply more effort than what is calculated. Give one reason why you think the coolie needs to apply effort.A block and tackle system of pulleys has a velocity ratio 4.
i) Draw a labelled diagram of the system indicating clearly the points of applications and direction of load and effort.
ii) What is the value of the mechanical advantage of the given pulley system if it is an ideal pulley system.i) What is meant by the term:
1. Amplitude 2. Frequency, of a wave?
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