Horrock's appar is used for-: (A) Wind velocity, (B) Chlorine demand, (C) Water contamination, (D) Coliform count
Answer is B. Ans. is 'b' i.e., Chlorine demand InstrumentUtilityHorrocks ApparatusChlorinator/ ChloronomeChloroscopeChlorine demand estimationMixing or regulating dose of chlorineMeasuring residual level of chlorine