Postulates

Q. The universal truths that are very trivial and self-evident are called ___ and ___.

1. postulates
2. rules
3. axioms
4. theorems

Q. Athira drew a straight line PQ. Her friend, Sanjeev put a point B at 3 cm from P. Aruna measured the whole line segment PQ to be 6.2 cm. The length of the segment BQ is ___ cm.

Q. Assumptions that are specific to geometry are called ____

1. postulates
2. axioms
3. theorems
4. theory

Q. Match the following based on Euclid's axioms and postulates:

1. Euclid's axiom
2. wholes are equal
3. more than parts
4. never meet

Q. Postulates are the assumptions which are specific to geometry.

1. False
2. True

Q. The calorific value of a fuel is expressed in a unit called ______.

Q. The calorific values of wood, diesel, natural gas and charcoal vary in the order –

1. Wood > Diesel > Charcoal > Natural gas
2. Wood > Diesel > Natural gas > Charcoal
3. Natural gas >Diesel> Wood > Charcoal
4. Natural gas >Diesel > Charcoal> Wood

Q. Which among the following has the highest calorific value?

1. Petrol
2. Wood
3. Coal
4. Cowdung cake

Q. The table below shows some fuels along with their calorific values and ignition temperatures.
$$\begin{array}{ccc}\text{Fuel}& \text{Calorific value (kJ/kg)}& \text{Ignition Temperature (}{}^{\text{o}}\text{C)}\\ \text{A}& \text{100}& \text{5}\\ \text{B}& \text{80}& \text{50}\\ \text{C}& \text{30}& \text{60}\\ \text{D}& \text{20}& \text{70}\end{array}$$
Which of these can be considered as an ideal fuel?

1. C
2. B
3. D
4. A

Q. Arrange the steps involved in the production of fire in the correct order.

1. Reaction with air
2. Release of energy
3. Burning of fuel
4. Ignition temperature attained