What are the strengths and weaknesses of the demographic transition model

The strengths of the demographic transition model are                              Useful for comparison between countries and for assessing development.

Shows a change through time.

Indicates the path other countries should follow.

Allows for forward planning,

Shows relationship between DTM and economic development.

The weaknesses of the demographic transition model are

The model assumes that all countries will develop - will countries like Ethiopia?

It assumes all countries will develop at the same speed (the UK took 200 years to industrialise. Yet countries like China have done so in 60 years)

Assumes countries will never reach a point where the population declines.

Assumes all countries' birth rates and death rates will follow the same pattern, it also doesn't consider government policy e.g. China's One Child Policy.  

The DTM has already had to be adapted to include the 5th stage.  

It also doesn't take immigration into account.

Explanation:

radiative zone

explanation    

radiative zone is the layer of the sun which energy is transferred away from the core by radiation. although, the core is the only part of the sun that produces an appreciable amount of heat through fusion. in fact, 99% of the energy produced by the sun takes place within 24% of the sun's radius.