Engineering

Boost your preparation with the latest Engineering MCQs with answers and explanations. Our collection covers civil engineering, electrical engineering, mechanical engineering, electronics, software engineering, and other core subjects. These multiple-choice questions are designed for students, competitive exam aspirants, and professionals preparing for NTS, PPSC, FPSC, CSS, PMS, PEC exams, university entry tests, and job interviews. Practice online with updated Engineering MCQs to strengthen concepts, improve technical knowledge, and perform better in exams and recruitment tests.

1395. In a laboratory test run, the rate of drying was found to be 0.5 x 10-3 kg/m².s, when the moisture content reduced from 0.4 to 0.1 on dry basis. The critical moisture content of the material is 0.08 on a dry basis. A tray dryer is used to dry 100 kg (dry basis) of the same material under identical conditions. The surface area of the material is 0.04 m²/kg of dry solid. The time required (in seconds) to reduce the moisture content of the solids from 0.3 to 0.2 (dry basis) is

2000
4000
5000
6000
✅ The correct answer is option C.

1399. In a gas-liquid shell and tube heat exchanger, the

Presence of a non-condensible gas decreases the condensing film co-efficient
Gases under high pressure are routed through the tube side, because high pressure gases are corrosive in nature
Gases to be heated/cooled is normally routed through the shell side, because the corrosion caused by the cooling water or steam condensate remain localised to the tubes
All of the above
✅ The correct answer is option D.