WorksheetsG8-PHY-L10 Combustion and Flame
Total questions: 20
Worksheet time: 10mins
Name
Class
Date
1.
What is combustion?
a)
A chemical process in which a substance reacts with oxygen to give off heat
b)
The process of burning a candle
c)
The act of lighting a matchstick
d)
The production of light and heat
2.
Which of the following is a combustible substance?
a)
Water
b)
Iron
c)
Wood
d)
Glass
3.
What is the difference between the burning of a candle and the burning of coal?
a)
Candle burns with a flame, coal does not
b)
Candle produces more heat than coal
c)
Candle burns faster than coal
d)
Candle produces less smoke than coal
4.
What are the three essential requirements for producing fire?
a)
Fuel, air, and water
b)
Fuel, oxygen, and heat
c)
Fuel, carbon dioxide, and heat
d)
Fuel, nitrogen, and oxygen
5.
Which zone of a flame is the hottest?
a)
Dark zone
b)
Luminous zone
c)
Non-luminous zone
d)
All zones have the same temperature
6.
What is the calorific value of a fuel?
a)
The amount of heat energy produced on complete combustion of 1 kg of fuel
b)
The temperature at which a fuel catches fire
c)
The cost of a fuel per unit
d)
The efficiency of a fuel
7.
Which of the following is a harmful product of burning fuels?
a)
Carbon dioxide
b)
Oxygen
c)
Water vapor
d)
Sulphur dioxide
8.
What is the best way to control a fire involving electrical equipment?
a)
Pour water on the fire
b)
Use a fire extinguisher
c)
Cover the fire with a blanket
d)
Let the fire burn out on its own
9.
Which type of combustion produces a sudden burst of flames without any apparent cause?
a)
Rapid combustion
b)
Spontaneous combustion
c)
Explosion
d)
Slow combustion
10.
Which of the following fuels has the highest calorific value?
a)
Wood
b)
Coal
c)
Petrol
d)
LPG
11.
What is the main reason for using CNG as a fuel in automobiles?
a)
It is cheaper than other fuels
b)
It produces less heat and light
c)
It is readily available
d)
It reduces pollution
12.
What is the main harmful effect of increased carbon dioxide in the air?
a)
Global warming
b)
Acid rain
c)
Respiratory diseases
d)
Corrosion of buildings
13.
Which of the following is an example of incomplete combustion?
a)
Burning of a candle
b)
Burning of coal
c)
Burning of LPG
d)
Burning of wood
14.
What is the purpose of a fire extinguisher?
a)
To supply oxygen to the fire
b)
To bring down the temperature of the fuel
c)
To cut off the supply of air to the fire
d)
To increase the heat of the fire
15.
Which of the following is a non-combustible substance?
a)
Wood
b)
Paper
c)
Iron nails
d)
Kerosene oil
16.
What is the colour of a candle flame?
a)
Red
b)
Blue
c)
Yellow
d)
Green
17.
What is the purpose of the dark zone in a flame?
a)
To produce heat
b)
To produce light
c)
To prevent the flame from spreading
d)
To vaporize the fuel
18.
Which of the following substances catch fire at different temperatures?
a)
Wood and coal
b)
Water and iron
c)
Glass and paper
d)
Kerosene oil and petrol
19.
What is the main reason for using CO2 as a fire extinguisher?
a)
It cools down the fuel
b)
It covers the fire like a blanket
c)
It increases the temperature of the fuel
d)
It produces oxygen
20.
Which of the following is an example of rapid combustion?
a)
Burning of a candle
b)
Burning of wood
c)
Burning of coal
d)
Burning of magnesium ribbon
100 %
