Smoking cigarettes can lead to emphysema. This occurs because. Answer: 5) A Emphysema is a condition in which lungs and air sacs are damaged, causing breathlessness. Breathlessness is caused by shortage…

Four 1000Ω resistors are connected as shown in the following circuit. Two of the resistors are changed to 900Ω. Changing which pair of resistors would make a current flow in…

One type of fission of 23892 U gives 9538 Sr and 13954 Xe as the main products.What else would be given off in the fission reaction? Answer: 3) D We…

You are told that three different gas jars contain carbon dioxide, hydrogen and oxygenrespectively.Which single method of testing for gases will enable you to identify all three gases? Answer: 2)…

The movement of air in and out of the lungs can be measured using a spirometer. The graph is a trace from a spirometer Which lettered arrow represents the tidal…

The sum of the roots of a quadratic equation is 7, the product of the roots is 9. What is theequation? Answer: 27) C To solve this, we need to…

The list below describes some events that occur during nuclear division. Indicate, by shading the appropriate circles on the answer sheet, which events occur during mitosis and which occur during…

For a rigid body performing small oscillations about a fixed horizontal axis, the period of oscillations is given by. where h is the distance of the centre of mass from…

The diagram shows the leg muscles of an athlete leaving the starting blocks for a race. Which muscles contract and which relax to bring about the change from position 1…

In water, the Fe^2+ ion bonds with water to form Fe(H2O)6^2+. In haemoglobin in the blood, five of the water molecules have been displaced. In the presence of air, the…