Important Questions Class 7 Science Chapter 15

Important Questions Class 7 Science Chapter 15 – Light

Science is a fascinating subject, but at the same time, it has some concepts which may be difficult to comprehend. Thus, students will have to make extra efforts to understand the concepts of Physics, Chemistry and Biology. 

Chapter 15 of Class 7 Science is about ‘Light’. The chapter includes topics around how right rays are emitted from a source, how the light rays travel through different mediums, and the various properties of light rays while travelling in any medium.

At Extramarks, we understand the importance of solving important questions and we take our role seriously to provide the best resource to the students and help them excel in life. Extramarks has been providing great online study resources for students from grades 1 – 12. Along with NCERT solutions and chapter-specific study notes, we have created Important Questions Class 7 Science Chapter 15 booklet that will help students to revise all the topics from the chapter while solving these questions. The questions are taken by our Science subject experts from various sources including NCERT textbooks, NCERT Exemplar books, past years’ question papers, CBSE sample papers, etc. 

At Extramarks, we highlight crucial concepts and questions from each chapter which help students with their studies right before their examinations. By solving the Important Questions Class 7 Science Chapter 15, the students will be familiar with the questions asked in final exams. Science is a subject which requires deep conceptual understanding, so cramming answers won’t help especially in higher classes. . 

So, while solving important questions, students must understand every concept to answer any question easily. This encourages the students to master the topic and increases their confidence in achieving high grades.  . 

Students should also try to understand the answer writing skill. For example, they can practise diagrams while answering the questions. Students can register on the Extramarks website and access our complete set of Class 7 Science Chapter 15 important questions

To speed up their learning and improve their academic performance, students can also refer to other study material on our Extramarks websites, including NCERT solutions, NCERT books, CBSE revision notes, past years’ question papers, etc. begin their preparation without any further delay. 

Important Questions Class 7 Science Chapter 15 – With Solutions:

Some of the vital questions and their solutions are given below which you will find in our Science Class 7 Chapter 15 important questions booklet.

Question 1. Write down the difference between virtual and real images.

Answer 1. The difference between virtual and real images are as follows: 

Question 2. How can a concave mirror be used to burn a piece of paper?

Answer 2. A concave mirror is also called a converging mirror. When sunlight passes through the concave mirror and reaches the piece of paper, it forms a sharp focus. The mirror and the paper are placed in the position for some time, and gradually the paper starts burning at the point of focus. It happens because of the convergence of all the light/heat energy at one point. In this way, a concave mirror burns a piece of paper.

Question 3. A virtual image bigger than the object can be produced by a-

(i) Concave lens 

(ii) concave mirror

(iii) convex mirror

(iv) plane mirror

Answer 3. (ii) concave mirror.

Explanation: A convex lens can produce a virtual and enlarged image when the object is placed between the pole and the focus of the lens. Both convex and concave mirrors form a virtual but diminished image of the object. At the same time, the plane mirror forms a virtual and same-sized image of the object.

Question 4. The rearview mirror of a bike is a plane mirror. A driver is reversing his bike at a speed of 2 metres per second. The driver sees the image of a truck parked behind his bike in his rearview mirror. With what speed does the image of the truck appear to approach, the driver will be

(i) 1 m/s

(ii) 2 m/s

(iii) 4 m/s

(iv) 8 m/s

Answer 4. (iii) 4 m/s.

Explanation: The speed of the bike is 2 m/s, which means the bike is reaching the truck at a speed of 2 metres per second. The separation between the bike and truck will be reduced at a double rate. The reason behind this is the image of the truck appearing to approach the driver with the speed of 2×2= 4 m/s.

Question 5. State the characteristics of the image formed by a plane mirror.

Answer 5. Following are the characteristics of the image formed by a plane mirror:

i) image formed by a plane mirror is erect.

ii) image is inverted laterally.

iii) image is of the same size as that of the object.

iv) the left side of the image appears on the right side and vice versa.

v) the distance between the image and the plane mirror is the same as the distance between the plane mirror and the object.

Question 6. If an object is placed at a distance of 0.5 m in front of a plane mirror, the distance between the object and the image formed by the mirror will be

(a) 2 m

(b) 1 m

(c) 0.5 m

(d) 0.25 m

Answer 6. (b) 1 m

Explanation: the image formed by a plane mirror is at an equal distance behind the plane mirror as the object is in front of it. So now,

The distance of the object from the plane mirror is 0.5 m

also, the distance of the image from the plane mirror is 0.5 m

Then the total distance between the object and plane mirror is 0.5 + 0.5, i.e. 1 m.

Hence, option (b) is correct.

Question 7. A rainbow is seen in the sky

(a) when the sun is in front of you.

(b) when the sun is behind you

(c) when the sun is overhead.

(d) only at the time of sunrise.

Answer 7. (b) when the sun is behind you.

Explanation: You can easily see a rainbow in the rainy season. Especially when the sun is behind you and the light is dim.

Question 8. You have three mirrors of different types. How will you identify each one of them?

Answer 8. One can easily identify the type of mirror based on the image formed of an object. There are mainly three types of mirrors. They are –

i) plane mirror – a plane mirror forms the image which is erect, virtual and of the same size as that of the object in front of it.

ii) convex mirror – a convex mirror forms an image that is erect, virtual and of small size to that of the object placed in front of it.

iii) concave mirror – a concave mirror forms an image that is inverted, virtual and diminished according to the object’s position.

Question 9. An image formed by a lens is erect. Such an image could be formed by a

(a) the convex lens provided the image is smaller than the object.

(b) the concave lens provided the image is smaller than the object.

(c) the concave lens provided the image is larger than the object.

(d) the concave lens provided the image is of the same size.

Answer 9. (b) concave lens provided the image is smaller than the object.

Explanation: a concave mirror forms an image of an erect, virtual and diminished object. 

Question 10. Write down four uses of a concave mirror.

Answer 10. The main uses of a concave mirror are as follows:

i) Used by ENT Specialists and dentists to see mouthparts.

ii) Used as a shaving mirror.

iii) makeup artists use a concave mirror.

iv) Used torches and car headlights to get a parallel light beam.

Benefits of Solving Important Questions Class 7 Science Chapter 15:

Students may face difficulty understanding the new concepts in Science. One way to tackle this is to practise important questions in the chapter. Chapter 15 Class 7 Science important questions cover all the  key topics, and these questions are prepared from the examination point of view and are frequently  asked in the exam. Solving important questions gives students a competitive edge and the confidence to face any challenging question with ease. 

Some of the benefits of referring to Important Questions Class 7 Science Chapter 15 are:

• The questions are collated after referring to various genuine sources that mainly include NCERT textbooks, NCERT exemplar books, past years’ question papers and various other sources. Hence students will find a  variety of questions of varying difficulty levels. Therefore, it is wise to take guided practice and be aware of the mistakes and maximise your potential by learning how to frame the right answer and get excellent grades in the examination.
• By practising different advanced level questions provided in the Important Questions Class 7 Science Chapter 15, students can thoroughly brush up on the concepts given in the chapter. This will help them revise the concepts again and give them a chance to analyse their shortcomings and overcome them before they face the final examinations.Also, stick to a study schedule and follow it religiously to come out with flying colours.
• The solutions to all the questions in important Questions Class 7 Science Chapter 15 follow the latest CBSE syllabus and NCERT guidelines. Experienced Science faculty members prepare our detailed answers. Students can fully rely on our study materials available on the website of Extramarks.Students need not refer to other books as Extramarks has all the solutions to their problems as it would be a total waste of time and may lead to unnecessary stress and anxiety.

We recommend students to take guided practice and help to be aware of their mistakes and maximise their potential by learning how to frame the right answer and develop the confidence to get 100% marks in the exams

Extramarks believes in incorporating joyful learning experiences through its own repository. It is one of  the leading online learning platforms that offer comprehensive learning solutions to students in classes 1-12. We also offer additional study and course materials. To access the most important resources, students can also click the links below:

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