Y8 HEAT BP COND,CONV,RAD

Which statement best describes how heat energy moves?

• Heat moves from a colder object to a warmer one.

• Heat moves randomly between objects regardless of temperature.

• Heat moves from a place of high heat concentration to a place of low heat concentration.

• Heat stays in one place unless forced to move.

Which statement best describes how a thermos minimises heat transfer?

• It increases molecular motion

• It uses a heater inside

• It has a vacuum to prevent conduction

• It keeps drinks airtight

Match each example to the type of heat transfer it shows (conduction, convection, or radiation):

Groups:

(a) CONDUCTION

,

(b) CONVECTION

,

(c) RADIATION

• Water boiling in a pot on a

  stove

• Warm air rising from a heat

  vent

• Pressing a hand against a

  cold window

• Petting a cat's warm body

• Feeling the warmth of

  sunlight on a chilly day

What causes your hand to feel warm when you hold a hot cup?

• Radiation from the cup

• Electrons transferring energy

• Molecules in your hand speeding up from direct contact

• Molecules in your hand slowing down

Conduction is to heat as communication is to

• speaking

• information

• energy

• hearing

At what point will a hot drink stop losing heat to its environment?

• When all its heat energy is used up

• When it reaches absolute zero and molecular motion stops

• When it reaches thermal equilibrium with its surroundings

• When it completely evaporates

What’s the term for the energy released as invisible light?

Why is radiation able to pass through the vacuum inside a thermos?

• A. It travels through conduction

• B. It is a form of invisible light

• C. It doesn’t need molecules to transfer heat

• D. Both B and C

Why are the insides of thermoses often shiny?

• To keep them clean

• To reflect heat through radiation

• To reflect heat through convection

• To block conduction

A bowl of hot soup is sitting in a room. What factor would make the soup

stay warm longer? Choose three.

• Placing the bowl on a cold surface

• Putting the soup in a thermos

• Increasing the temperature in the room

• Covering the top of the bowl

• Placing the bowl near an open

  window