Chap 2

Question 1

What is the formula for Density

Answer 1

Mass/Volume

Question 2

What is the S.I. unit for density?

Answer 2

kg/m cube

Question 3

How do you define the strength of a material?

Answer 3

The ability of a material to withstand an applied load without breaking or tearing

Question 4

How do you define the hardness of a material

Answer 4

The ability to scratch another material

Question 5

Why is a cooking pot made of aluminium whilst its handle is made of plastic?

Answer 5

Aluminium is a good heat conductor but plastic is not

Question 6

What is the hardest mineral such that it is used in drill bits to cut rocks

Answer 6

Diamond

Question 7

Electrical wires are made of ________ which is a good electrical conductor and the outside covering on the wires is made of ________ which is a poor electrical conductor

Answer 7

Copper

Plastic

Question 8

The bulb is made of ______ to allow _______ to pass through and radiated in all directions

Answer 8

Glass

Light

Question 9

The filament is made of tungsten which has a high _______ point, to withstand the high ________

Answer 9

melting

temperature

Question 10

The stem is made of glass and the cap is filled with ________ insulation to prevent the conduction of _______.

Answer 10

ceramic

electricity

Question 11

The bulb is filled with _______ gas to prevent the filament wire to be ________ off

Answer 11

inert

burnt

Question 12

Define independent variable

Answer 12

The independent variable is the factor that will affect the result of the experiment

Question 13

Define dependable variable

Answer 13

The dependent variable is the factor that will affected by the independent variable

Question 14

Define controlled variables

Answer 14

The controlled variables are the factors that are kept constant

Question 15

What plastics are strong but not tough, brittle and cannot be stretched without breaking

Answer 15

Rigid Plastcis

Question 16

Define flexible plastics

Answer 16

Flexible plastics can be stretched easily, not strong but tough

Question 17

To float on water, the submarine forces the water out of the main ballast tank. The ______ of the submarine _______ when it fills its main ballast tank with water and _______ when it forces water out of its main ballast tank

Answer 17

density
increases
decreases

Question 18

What temperature is water most dense at?

Answer 18

4 degrees Celsius

Question 19

Why does recycling paper help reduce the level of carbon dioxide in the atmosphere?

Answer 19

There are more trees to decrease the amount of carbon dioxide through photosynthesis

Question 20

What material is a poor conductor of heat, not transparent, not brittle and not made by weaving materials together
Metals
Plastics
Ceramics
Glass
Fibre

Answer 20

Plastic

Question 21

What material is a poor conductor of heat, not transparent, but brittle
Metals
Plastics
Ceramics
Glass
Fibre

Answer 21

Ceramics

Question 22

What material is a poor conductor of heat and transparent
Metals
Plastics
Ceramics
Glass
Fibre

Answer 22

Glass

Question 23

What material is a good conductor of heat
Metals
Plastics
Ceramics
Glass
Fibre

Answer 23

Metals

Question 24

State 4 characteristics of chalk

Answer 24

Permeable
less dense than water
Splits when hit by hard objects
Wears off when undergoing friction

Question 25

State 2 characteristics shared by marble and granite?

Answer 25

It does nit split when hit by hard objects and is not permeable