Book Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1909 edition. Excerpt: ... MECHANICS PASCAL'S PRINCIPLE 135. A cork 1 sq. in. in cross section is forced with a pressure of 30 lb. into the neck of a cylindrical bottle filled with water. The bottom of the bottle is 6 in. in diameter inside. Find the pressure on the bottom, caused by the cork. 136. A closed rectangular tank is 20 cm. high and has a base 30 X 40 cm. Through a hole 1 cm. square in the top it is filled with water. If ai plug is then driven into this hole with a pressure of 500 g., what additional pressure will be exerted upon (a) the bottom? (6) each side? (c) the top? 137. A cubical tank holds 1728 cu. in. of water. Through an opening 1 in. square in the top a plug is pushed with a force of 50 lb. (a) What additional pressure does this cause on the inside of the tank? (6) How would the result be changed if the opening were halfway down the side instead of in the top? 138. A barrel full of vinegar is lying on its side with the bung uppermost. The head of the barrel has an inside diameter of 20 in. The inner diameter of the bung is 2 in. The bung is driven in so that it exerts a pressure of 20 lbs. upon the liquid directly beneath it. What is the additional pressure upon the head? 139. The area of the safety valve of a steam boiler (Fig. 1) is 3 sq. in. What weight must be placed directly on the valve, D, to keep it from blowing off (i.e. lifting) until the pressure in the boiler is 50 lb. per square inch? 8 140. The diameter of the safety valve of a steam boiler is 1 in. and the weight placed directly on it is 20 lb. At what pressure will it blow? Counterpoise 141. The area of the safety valve of a steam boiler is 2 sq. in. and the weight upon it is 50 lb. When the steam within lifts the valve, what is the boiler pressure per square inch? 142. A...