MCQ - CBSE Class 9 Science A boy strikes one end of a long pipe with a stone. Another boy who keeps his ear close to the other end of pipe heard two sounds in a short interval of time. Explain, why. 10/04/2023 Ajit kumar 80 Views 0 Comments Read more
MCQ - CBSE Class 9 Science Define frequency, amplitude and speed of a sound wave. 10/04/2023 Ajit kumar 75 Views 0 Comments Read more
MCQ - CBSE Class 9 Science Explain how human ear works in the transmission of sound wave to the brain. 10/04/2023 Ajit kumar 88 Views 0 Comments Read more
MCQ - CBSE Class 9 Science What is ‘Ultrasound’? Explain how defects in a metal block can detected using ultrasound. 10/04/2023 Ajit kumar 90 Views 0 Comments Read more
MCQ - CBSE Class 9 Science What does the acronym SONAR stand for? 10/04/2023 Ajit kumar 97 Views 0 Comments Read more
MCQ - CBSE Class 9 Science Even if a loud explosion were to take place at any place on the moon, it would not be heard at a nearby point. Give reason. 10/04/2023 Ajit kumar 66 Views 0 Comments Read more
MCQ - CBSE Class 9 Science Why the stage of an auditorium has curved background, curtains, carpets and false ceiling? 10/04/2023 Ajit kumar 73 Views 0 Comments Read more
MCQ - CBSE Class 9 Science Why the astronauts talk to each other through radio telephone ? 10/04/2023 Ajit kumar 71 Views 0 Comments Read more
MCQ - CBSE Class 9 Science Give four practical uses of ultrasonic vibrations. 10/04/2023 Ajit kumar 65 Views 0 Comments Read more
MCQ - CBSE Class 9 Science State three conditions necessary for sound to be heard. 10/04/2023 Ajit kumar 92 Views 0 Comments Read more