(1) When 0.2kg of brass at 100°C is dropped into 0.5kg of water at 20°C, calculate the specific heat of brass.
(2) A 10kW drilling machine is used to drill in a small aluminium block of mass 8kg. How much is the rise in temperature of the block in 2.5minutes. Assuming 50% of power is lost to the surroundings. Specific heat of aluminium= 0.91 J/g°C.
(3) The wavelength and frequency of sound wave in a certain medium is 40cm and 825Hz respectively, keeping the medium unchanged, if the wavelength is changed to 32cm, calculate the resulting frequency?