Q1: To avoid the force of surface tension in an inclined manometer, the minimum angle of inclination is

ANS:C - 4°

angle of 4° for avoiding the force of surface tension in an inclined manometer may not be a universally accepted standard or requirement. In practice, the minimum angle of inclination to avoid the influence of surface tension in an inclined manometer can vary depending on several factors, including the specific properties of the liquid being measured, the diameter of the manometer tube, and the desired accuracy of the measurement. While it is true that increasing the angle of inclination can help minimize the effects of surface tension, excessively steep angles may make the manometer difficult to read and use effectively. In general, an angle of inclination greater than 3° may indeed help reduce the influence of surface tension, but the choice of angle should also consider practical considerations such as readability and ease of use. Therefore, while an angle of 4° or greater may provide some improvement in reducing surface tension effects, the choice of angle should be made based on the specific requirements and constraints of the measurement application. It's always best to consult relevant standards, guidelines, or expert recommendations when determining the appropriate angle of inclination for an inclined manometer.