O centro de massa é onde se supõe estar concentrada toda a do corpo e onde se considera estarem aplicadas todas as que nele atuam. O centro de massa move-se com a mesma do conjunto de pontos do corpo. Um corpo pode ser representado pelo seu centro de massa, se:
• As variações da energia forem desprezáveis
• Os corpos forem ou não deformáveis
• Existir apenas movimento de , ou seja, todos os pontos se movem à mesma .

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

Afour cylinder four-stroke in-line engine has a stroke of 160mm, connecting rod length of 150mm, a reciprocating mass of 3kg and its firing order is 1-3-4-2. the spacing between cylinders is 100mm. i. show that the engine is in balance with regard to the primary inertia forces and primary 3. a and secondary inertia couples. li determine the out of balance secondary inertia force ii. propose ways of balancing this out of balance force and discuss the challenges that will arise

At 12 noon, the count in a bacteria culture was 400; at 4: 00 pm the count was 1200 let p(t) denote the bacteria cou population growth law. find: (a) an expression for the bacteria count at any time t (b) the bacteria count at 10 am. (c) the time required for the bacteria count to reach 1800.