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Question 1

State how solid expands when heated

Answer 1

Particles in solid vibrate at fixed position
Heated: Vibrate faster -> further apart from one another -> solid volume increase

Question 2

State how solid contract

Answer 2

Cooled: Particles vibrate slower -> move closer to on another -> solid volume decrease

Question 3

State how gas & liquid expands

Answer 3

Particles move freely
Heated -> move faster & randomly -> distance between particles increase -> volume increase

Question 4

State how liquid and gas contract

Answer 4

Cooled: Move slower & closer to one another -> volume decrease

Question 5

What is the use of E & C in thermometer

Answer 5

Mercury is a heat conductor -> E & C

Question 6

Why is there gaps in railway tracks

Answer 6

Enable them to expand in hot weather
Without gap -> track buckle & overlap -> derail

Question 7

State E & C in steel bridges

Answer 7

Build w/ rollers and gap on one end
Hot weather -> can expand

Question 8

State the function of bimetallic strip

Answer 8

Used in device that depend on temperature regulation

Question 9

State how bimetallic strip works

Answer 9

Made of two different types of metal strips: E & C at different rates

Question 10

State example of bimetallic function in fire alarm system

Answer 10

Exposed to heat from fire -> copper strip expand faster than steel strip -> bend towards contact point -> completes system & alarm ring

Question 11

State the rate of E & C of different metals

Answer 11

Aluminum
Bronze
Copper
Iron

Question 12

How to open tight lid

Answer 12

Submerge bottle in hot water -> expand & open

Question 13

How to undent a tennis ball

Answer 13

Put in hot water -> air in ball expands

Question 14

Why electric transmission cables on poles are hung loosely

Answer 14

Prevent from snapping at night -> contract

Question 15

Why are fuel tanks painted bright colours

Answer 15

Bright colours do not absorb a lot of heat -> evaporation of fuel reduced

Question 16

Ability to absorb / radiate heat depends on

Answer 16

Type -> shiny / dull
Colour -> Bright / Dark

Question 17

State the relation between type and colour of surface with absorption and radiation of heat

Answer 17

Dark & dull -> better heat A & R
White & Shiny -> weaker

Question 18

What is Green Building Concept

Answer 18

Reduce effect of rapid development on the environment & health

Question 19

What are the features of green buildings

Answer 19

High energy efficiency -> solar energy / renewable energy
Good water flow system, air circulation & lighting
Recycled materials

Question 20

What is the fastest heat transfer method

Answer 20

Radiation -> does not use any medium to propogate

Question 21

Is air a good insulator or conductor

Answer 21

Insulator

Question 22

What happens if insecticide can is thrown into rubbish dump

Answer 22

High heat (weather / burning) increase pressure of can -> explode