I will also be sharing three common Light questions that you can familiarise yourself with ahead of your Science examinations.<\/p>\n
You may also choose to watch the video here<\/a>.<\/p>\n Source: CHIJ St. Nicholas Girl’s School \u2014 P6 SA1 Examination Paper [Q36]<\/em><\/p>\n Let us first define what the question means by transparency<\/strong>. Transparency refers to how much light is able to pass through the material.<\/p>\n There are three different types of transparency of a material:<\/p>\n When no material is placed at position P, the light sensor shows a reading of 100 units. <\/strong>The 100 units in this question represent the brightness of the torch.<\/p>\n Materials X, Y and Z are placed at Position P, one at a time, and the readings recorded by the light sensor are shown in the table below.<\/strong>\u00a0<\/strong><\/p>\n Let us examine the results of the experiment. The numbers indicate the amount of light recorded.<\/p>\n Bearing in mind that the total amount of light emitted from the torch is 100 units, we can deduce that:<\/p>\n “Based on the table, compare the transparency of materials X and Z.”<\/strong><\/p>\n Some students will answer this question as \u201cX is transparent, while Z is translucent.\u201d, simply stating the properties of each material.<\/p>\n Unfortunately, that is not the answer that teachers are looking for.<\/p>\n X allows more light to pass through it than Z.<\/p>\n Source: CHIJ St. Nicholas Girl’s School \u2014 P6 SA1 Examination Paper [Q36]<\/em><\/p>\n What property of light allows this set-up to work?<\/p>\n Objects move between the light sensor and the light source. The light sensor registers the amount of light it receives. The brightness detected rises and falls regularly as Object A passes between them.<\/p>\n Most students are quick to conclude that the light is blocked because Object A is opaque and<\/strong> does not allow light to pass through<\/strong>.<\/p>\n \ud83d\udca1 However, the term “opacity” is a property of the material<\/strong> and not a property of light!<\/p>\n<\/blockquote>\n The correct answer is light travels in a straight line<\/strong>.<\/p>\n If light could go around any obstruction, the opacity or transparency of any material would be completely irrelevant to the set-up as light would simply bend to reach the sensor!<\/p>\n However, as light travels in a straight line, any object passing between it and the sensor would be blocked.<\/p>\n This is shown on the graph by the sensor readings dropping to 0 units. If light could bend around any obstruction\u2026<\/p>\n Then the sensor would register as 100 forever, making the set-up redundant.<\/p>\n \u2b50\ufe0f Tip 1: <\/strong>One trap that students tend to fall for is the duration of the time stated in the question<\/strong>.<\/p>\n Some questions will include a graph that reads 20 seconds, but only requires students to derive 8 seconds’ worth of data.<\/p>\n<\/blockquote>\n Thankfully, this particular question is quite straightforward. Let\u2019s examine the graph!<\/p>\n Source: CHIJ St. Nicholas Girl’s School \u2014 P6 SA1 Examination Paper [Q36]<\/em><\/p>\n In order to read this graph, we must first understand how the reading is derived from the sensor.<\/p>\n As mentioned above, whenever an object passes between the light and the sensor, the light is blocked, causing the sensor to detect 0 units of light. This means that the line on the graph will similarly drop to 0.<\/p>\n Therefore, you will need to count the number of times the line touches the bottom of the graph.<\/p>\n On the timeline, it will be as follows: (2 to 4 seconds), (6 to 8 seconds), (10 to 12 seconds), (14 to 16 seconds).<\/p>\n That\u2019s 4 times, so the answer is 4 objects<\/strong>.<\/p>\n 4 objects.<\/p>\n “The light source and the sensor are placed 5 cm above the belt. State whether an object less than 5 cm in height can be counted by the light sensor. Give a reason for your answer.”<\/strong><\/p>\n Let\u2019s visualise this scenario:<\/p>\n No, because the object is shorter than 5 cm, the light from the torch, which travels in a straight line, cannot be blocked by the object.<\/p>\n \u2b50\ufe0f Tip 2: <\/strong>It is extremely important that students include the property of light (i.e. light travels in a straight line) in the answer.<\/p>\n<\/blockquote>\n “When identical objects B made of material Y were placed on the moving belt, the number of objects counted in 18 seconds were fewer. The data recorded is as shown below.”<\/strong><\/p>\n Source: CHIJ St. Nicholas Girl’s School \u2014 P6 SA1 Examination Paper [Q36]<\/em><\/p>\n “Based on the above graph, state a difference between object A and B.”<\/strong><\/p>\n Object B is made of Material Y. This is the same material used to make Object A. We can immediately rule out a difference in opacity<\/strong>.<\/p>\n Next, let us count the number of objects that passed through the sensor in 18 seconds:<\/p>\n That\u2019s 3 objects. Not only are there less objects passing through, but the amount of time it takes for the object to pass through the sensor has increased!<\/p>\n What does this mean? It means that Object B is larger than Object A<\/strong>. Its larger width causes it to block the light for a longer period of time as it takes a longer time for it to pass through the pathway of the light.<\/p>\n Object B is larger than Object A.<\/p>\n Instead of describing how light is reflected off the object, you need to describe how the light from the object\/light source travels into their eyes directly.<\/p>\n A typical item used for this scenario is a handphone since the screens are backlit and do not require an additional light source to be visible.<\/p>\n In this scenario, you must describe how the light from the lamp reflects off the object into the eyes, allowing the person in the question to see the object.<\/p>\n You may also be expected to define shadows and explain how shadows are formed.<\/p>\n \ud83d\udca1 Shadows<\/strong> are formed when light from a light source, which travels in a straight line, is blocked by an object that is translucent or opaque.<\/p>\n<\/blockquote>\n You will need to be able to relate these shadows to three properties: shape, size and shade.<\/p>\n Many of such questions will describe a torch shining on an object (or a combination of objects) from different angles or distances.<\/p>\n You will be expected to predict the likely shape and size of the shadow formed from a particular angle of the torch and vice versa.<\/p>\n For the last property, shade, it is determined by the opacity<\/strong> of the material. A material that is opaque will cast a darker shadow than a material that is translucent, and a material that is transparent will cast no shadow at all.<\/p>\n I have covered the essential concepts on the topic of Light<\/a> that you will need to be familiar with in order to do well in your Science examinations. I hope that you also spend some time looking through the three other common questions that I have highlighted so that you will not be caught off guard during your Science examinations, but can tackle them confidently and accurately.<\/p>\n Check out our other Light<\/a> articles and stay tuned for more articles! \ud83d\ude42<\/p>\n [\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row disabled_on=”off|off|off” admin_label=”CCI” _builder_version=”4.21.0″ custom_margin=”0px||” custom_padding=”0px||” global_module=”239753″ saved_tabs=”all” collapsed=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_divider color=”#898989″ admin_label=”Divider” _builder_version=”4.16″ locked=”off” global_colors_info=”{}”][\/et_pb_divider][et_pb_image src=”https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2019\/05\/The-Pique-Lab-CCI-Science-Course-CTA.png” align=”center” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” admin_label=”CCI” _builder_version=”4.16″ z_index_tablet=”500″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” text_text_color=”#333333″ text_font_size=”18px” text_orientation=”center” global_colors_info=”{}”]<\/p>\n If you like our methodology, we’ve some upcoming workshops:<\/p>\n [\/et_pb_text][et_pb_text _builder_version=”4.16″ text_font=”geomanist-medium||||||||” text_text_color=”#f44a4a” text_font_size=”18px” text_line_height=”2em” text_orientation=”center” global_colors_info=”{}”]<\/p>\n P3 Complete Concept Integration\u2122 Science Course<\/strong><\/a> [\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section]<\/p>\n","protected":false},"excerpt":{"rendered":" <\/p>\n","protected":false},"author":55,"featured_media":242564,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"","om_disable_all_campaigns":false,"_lmt_disableupdate":"no","_lmt_disable":"","footnotes":""},"categories":[8,7,3,47],"tags":[],"post_folder":[],"modified_by":"Jaimie Aberia","_links":{"self":[{"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/posts\/240034"}],"collection":[{"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/users\/55"}],"replies":[{"embeddable":true,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/comments?post=240034"}],"version-history":[{"count":19,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/posts\/240034\/revisions"}],"predecessor-version":[{"id":244467,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/posts\/240034\/revisions\/244467"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/media\/242564"}],"wp:attachment":[{"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/media?parent=240034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/categories?post=240034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/tags?post=240034"},{"taxonomy":"post_folder","embeddable":true,"href":"https:\/\/thepiquelab.com\/blog\/wp-json\/wp\/v2\/post_folder?post=240034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Read Also:<\/h3>\n
\n
Let’s Get Started On This Question!<\/strong><\/h2>\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-01-1024x1001.png\")
<\/p>\n\n
\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-02.png\")
<\/p>\nLet’s Analyse Part (A)<\/strong><\/h2>\n
Suggested Answer For Part (A)<\/strong><\/h2>\n
Let’s Analyse Part (B)<\/strong><\/h2>\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-03-1024x409.png\")
<\/p>\n\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-04.png\")
<\/p>\n![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-05.png\")
<\/p>\n\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-06.png\")
<\/p>\nSuggested Answer For Part (B)<\/strong><\/h2>\n
Let’s Analyse Part (C)<\/strong><\/h2>\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-07.png\")
<\/p>\nSuggested Answer For Part (C)<\/strong><\/h2>\n
\n
Let’s Analyse Part (D)<\/strong><\/h2>\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-08.png\")
<\/p>\n\n
Suggested Answer For Part (D)<\/strong><\/h2>\n
Common Examples Of How Light May Be Tested During Examinations<\/strong><\/h2>\n
1) The Light Source Is Also The Object To Be Seen<\/strong><\/h3>\n
2) The Light Source Is NOT The Object To Be Seen<\/strong><\/h3>\n
3) Formation Of Shadows<\/strong><\/h3>\n
\n
![](\"https:\/\/thepiquelab.com\/blog\/wp-content\/uploads\/2023\/04\/Light-09.png\")
<\/p>\nConclusion<\/strong><\/h2>\n
P4 Complete Concept Integration\u2122 Science Course<\/strong><\/a>
P5 Complete Concept Integration\u2122 Science Course<\/strong><\/a>
P6 Complete Concept Integration\u2122 Science Course<\/strong><\/a><\/p>\n