Calendar: 1870-1871 Page 530

530 APPLIED SCIENCES Find the conditions for sensibility in an ordinary balance Two planes whose inclinations to the horizon are 30 and 45 respectively are placed back to back On the former rest9 weight of 10 lbs which is connected by string passing over the top with weight resting on the other Find the magni- tude of the second weight the planes being smooth ladder is supported by leaning against rough wall its foot resting on horizontal plane Find the position that motion may be on the point of taking place if the co-efficient of friction between the ladder and the wall and the ladder and ground be the same in each case and equal to μ stone is let fall from tower 200 feet high and after one second another is thrown after it with what velocity must the second be thrown that both may reach the ground at the same instant Two weights half pound each are connected by string passing over smooth pulley and an ounce is added to one of them Find the velocity of the system after minute has elapsed and if the string be then cut how far will they be apart at the next minute Through what distance must force equal to weight of lb act on mass of 644 lbs in order to increase its velocity from 24 to 36 feet per second Find the range and time of flight of projectile on plane inclined to the horizon at given angle 10 marble is let fall through 20 ft how high will it rebound and how long will it go on rebounding if SECOND AND THIED YEARS Find the resultant of two forces which acton body in parallel directions Explain what is meant by the centre of such forces and show how it is found when they act in opposite parallel directions Explain the peculiarities which arise when the two forces are equal