Week 7

• Heat source


  Anything that gives off heat
• The sun is the main heat source of the earth
• The sun is the main source of light as it reflects or absorbed by objects on earth
• Absorbed light usually increases the energy in an object causing the object to heat up
• Solar energy


  The sun radiates light and heats our solar energy
• Solar energy


  • Essential to agriculture
  • Cultivating land
  • Producing crops
  • Raising livestock
• Solar techniques

  1. Crop rotation

  2. Increased harvest
• Beneficial effects of sun to human body

  • Maintains strong bones
  • Strengthens immune system
  • Protects from type 1 diabetes
  • Helps wounds heal
  • Helps feel more alert
• Harmful effects of sun to human body

  • Short-term skin damage
  • Long-term skin damage
  • Heat stroke
  • Dehydration
  • Hives
• Sunlight is a key energy source for all plants
• Sunlight includes generating the production of vitamin D and supporting bone health
• Harmful effect of sun

  • Dehydration caused by not drinking enough fluid or losing more fluid than taken in
• Playing under the sun at noon time is not a good practice
• Looking directly at the sun is not a good practice
• Lying on beaches all day is not a good practice
• Staying under the sun the whole day is not a good practice
• Exposing eyes to the bright glaring light of the sun is not a good practice
• Good practices to avoid harmful sun effects

  • Wearing a white brim hat on sunny days
  • Using an umbrella on sunny days
  • Wearing sunglasses in beaches
  • Applying sunblock lotion
  • Wearing long sleeves and trousers when working