Question

At 9:00 a.m. Monday morning, Thomas fills a beaker with water and places it in the corner of the classroom. At 1:00 p.m. on Tuesday, Thomas examines the beaker and notices that the water level is 42 milliliters. At 11:00 a.m. on Wednesday, the water level has dropped to 31 milliliters. If the evaporation of the water follows a linear function, at what time will the beaker be empty?.

Answer 1

Answer is: will the beaker be empty Saturday 1:00 am.

l₁ = 42 mL; water level at Tuesday.

l₂ = 31 mL; water level at Wednesday.

Δl = l₁ - l₂.

Δl = 42 mL - 31 mL.

Δl = 11 mL; difference between water levels.

Δt = 22 h; difference in time.

rate of evaporation = Δl ÷ Δt.

rate of evaporation = 11 mL ÷ 22 h.

rate of evaporation = 0.5 mL/h.

t = 31 mL ÷ 0.5 mL/h.

t = 62 h; time needed for empty the beaker.

Answer 2

Given the data level decreased to 31 milliliters from 42 milliliters for 22 hrs (the difference of height is 11 milliliters) we take the rate of height depreciation of 0.5 mL/ hour. In this case, to drain out all 31 milliliters, a total of 62 hrs must be alloted. 62 hours is equal to 2 days and 14 hrs. Hence the day which the beaker becomes empty is Saturday at 1 am.