Peka Science Year 4

Date : 13-8-2010 Activity Code : 4 /3/ 1.1/ 11 Theme : 3 Investigating Materials Topic : 1 Properties of materials Learning Outcomes : 1.1.11 Classify materials based on their abilities to allow light to pass through Aim : To investigate the relationship between the types of materials and the ability of light to pass through them. Apparatus : Glass prism,tap water, tracing paper , film negative, black paper, wooden block, torch Method : 1.      Pupils are given the apparatus such as glass prism,tap water, tracing paper , film  negative, black paper, wooden block and a torch. 2. Switch on the light. 3. Light is shone on all the objects. 4. The light is observed to see whether it passes     through the objects. Observation : Objects Light can penetrate through Some of the light can penetrate through Light cannot penetrate through Glass prism Tap water Tracing paper Film negative Black paper Wooden block Discussion : 1. The ability of the light to penetrate objects can be used to classify objects. The following objects can be classified as shown in figure 1.              Manifying glass         wooden box                 sunglass              Carboard                   haze                             black ink 2. Which objects cause darker shadows to form when light passes through them?     Opaque. 3. Sunglasses are made of  ( opaque / translucent ) materials, so that ( some / all )     of the sunlight is blocked?     Conclusion   :    Objects can be classified according to the ability of light to                            pass through them : (a)    Transparent – light can completely pass through. (b)   Translucent – only some of the light is allowed to pass through (c)    Opaque – light cannot pass through at all.