100 g of water at 25 °C is poured into an insulating cup. 50 g of ice at 0 °C is added to the water. The water is stirred until the temperature of the water has fallen to 0 °C. 18 g of ice remains unmelted. The specific heat capacity of water is 4.2 J / g °C. Which value does this experiment give for the specific latent heat of fusion of ice? B 330 J / g Q lost H2O = m c t
= 100x4.2x25=10500 J
L = Q gained by ice /m
= 10500 / 50-18
= 328.1J/g

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s. part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.