Aim: (a) To prove that air has mass/weight. Procedure: Take a stick or a staw. Tie a thread at its centre and hang it so that it so that it remains horizontal. Tie two opposite ends of the stick as shown in the diagram. keep the stick in prefect horizontal position. Now remove one balloon and inflate it with air. Again tie it at the original end.

Observation: Tick ✓ the appropriate answers:
1) Does the stick remain in the horizontal position now?( Yes/No)
2) What happens to the stick at the side of the inflated balloon?( It goes up/ It goes down)

Influence:​

We want to calculate the total metabolic heat generated by a singing canary taking into account heat transfer by radiation, convection and exhaling air. the air temperature is 20 oc, canary’s body internal and surface temperature is 33oc, external body surface convective heat transfer coefficient is 25.2 w/m2 .k, temperature difference between the inhaled and exhaled air is 4.3 oc, the ventilation rate is 0.74 cc of air per second, specific heat of air is 1.0066 kj/kg.k and density of air is 1.16 kg/m3 . assume the canary’s body to be a cylinder with 7 cm diameter and 9 cm length, and heat exchange is from the side as well as the top and bottom of cylinder. calculate 1) the net rate of heat lost by radiation, assuming heat gained by the bird through radiation from the surroundings is 11.5 w; 2) rate of heat transferred by convection to the surrounding air; 3) rate of heat transferred in the exhaling air without considering any internal evaporation; 4) total metabolic power.

The items in the following list are all units of matter. which is the smallest unit that retains the properties of the matter? a.) atom b.) compound c.) electron d.) element

How are positive ions different from neutral atoms