एक ठोस लंब वृत्तीय बेलन (cylinder) को समान आधार वाले एक ठोस अर्धगोले (hemisphere) से जोड़ा गया है। बेलन की ऊंचाई और आधार की त्रिज्या का अनुपात ज्ञात कीजिए ताकि संयुक्त गुरुत्व केंद्र आधार के केंद्र पर हो।

Calculate the magnitude of the smaller force if two forces act at an angle of 120° and the larger force has a magnitude of 40 N. (Note: The resultant of these two forces is perpendicular to the smaller force.)

The resultant of two like parallel forces P and Q passes through a point O. The resultant still passes through O when P and Q are increased by R and S respectively, as well as when P and Q are replaced by Q and R respectively. The force S is equal to: