Q3. Draw the perpendicular bisector of XY whose length is 10.3 cm.
(a) Take any point P on the bisector drawn. Examine whether PX = PY.
(b) If M is the mid point of XY , what can you say about the lengths MX and XY?
8 Water is pouring into a cubiodal reservoir at the rate of 60 litres per minute. If the volume of reservoir is , find the number of hours it will take to fill the reservoir.
13. Abida and Ramesh were doing an experiment in which water was to be heated in a beaker. Abida kept the beaker near the wick in the yellow part of the candle flame. Ramesh kept the beaker in the outermost part of the flame. Whose water will get heated in a shorter time?
11. In an experiment 4.5 kg of a fuel was completely burnt. The heat produced was measured to be 180,000 kJ.Calculate the calorific value of the fuel.
5. Give reasons.
(c) Paper by itself catches fire easily whereas a piece of paper wrapped around an aluminium pipe does not.
2. Fill in the blanks.
(a) Burning of wood and coal causes_________ of air.
(b) A liquid fuel, used in homes is_________ .
(c) Fuel must be heated to its___________ ___________ before it starts burning.
(d) Fire produced by oil cannot be controlled by__________ .
11. Complete the word puzzle
1. Species on the verge of extinction.
2. A book carrying information about endangered species.
5. Consequence of deforestation.
1. Species which have vanished.
3. Species found only in a particular habitat.
4. Variety of plants, animals and microorganisms found in an area.