Water at the Antarctica usually exits as ice, making it very difficult to use the water or conduct experiment requiring the water to be in liquid state. A coffee addicted physicist stationed at a research base requires about 0.8 kg of ice for his coffee on the hour. a. How much heat is required to convert 0.8 kg of ice at -35 "C into steam at 100 C7 b. Plot the temperature - energy graph for the processes in (a). 5] [5] c. The surface tension of water was determined in a laboratory by using the drop weight method. 100 drops were released from a burette the inner diameter of whose opening is 1.8 mm. The mass of the droplets was 3.78 g. 1. Determine the surface tension of the water and comparing it with the tabulated value, i. Calculate the relative error of the measurements: [6] [4]

water or conduct experiment requiring the water to be in liquid state. A coffee

addicted physicist stationed at a research base requires about 0.8 kg of ice for

his coffee on the hour.

a. How much heat is required to convert 0.8 kg of ice at -35 °C into steam

at 100°C?

[5]

b. Plot the temperature - energy graph for the processes in (a). [5]

C. The surface tension of water was determined in a laboratory by using

the drop weight method. 100 drops were released from a burette the

inner diameter of whose opening is 1.8 mm. The mass of the droplets

was 3.78 g.

i. Determine the surface tension of the water and, comparing it

with the tabulated value,

161

ii. Calculate the relative error of the measurements.

b

explanation:

96.77 amp

explanation:

rl = 250/100 = 2.5 ohms.

egl = 250 + (100 × 0.1) + 2 = 262 v.

at 700 r.p.m., eg2 = 262 × 700/1000 = 183.4 v.

if ia is the new current, then eg2 - 2 - (ia × 0.1) = 2.5 ia

which means this will give ia = 96.77 amp.