MEDIUM
7th ICSE
IMPORTANT
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What is an echo? When is an echo heard?

Important Questions on Sound

HARD
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q IV
Write the causes and steps to reduce noise pollution. (Any three of each)
MEDIUM
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q V

Differentiate between the following:

Loudness and pitch

MEDIUM
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q V

Differentiate between the following:

Music and noise

HARD
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q V
Differentiate between audible and inaudible sounds.
EASY
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q VI
A girl stands at a distance of 240 m away from a wall. She shoots a rifle and hears an echo after 1.2 s. Calculate the velocity of sound.
EASY
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q VI
A sonar signal sent down from a ship, is reflected from the ocean floor and detected by a hydrophone 0.6 s later. Calculate the depth of the ocean. Take the speed of sound in sea water as 1500 m s-1.
EASY
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q VI
A ship on the surface of water sends a signal and receives it back after 4 s from a submarine inside the water. Calculate the distance of the submarine from the ship. The speed of sound in water is 1450 m s-1.
MEDIUM
7th ICSE
IMPORTANT
Innovative Physics>Chapter 7 - Sound>EVALUATE YOUR UNDERSTANDING>Q 1
Rohit called up to talk to Reena but her brother Vicky received the call. When Vicky said 'Hello', Rohit immediately recognised his voice without any introduction that it is not Reena on the other side. How did Rohit recognise the voice without seeing the person?