What is echo?

Important Questions on Practice Paper 4

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 25

Aditi clapped her hands near a cliff and heard the echo after 4 seconds. What is the distance of the cliff from her if the speed of sound is taken as $346 \mathrm{m} {\mathrm{s}}^{-1}$.

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 25

What is the nature of sound waves?

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 25

How does speed of sound change with temperature of medium?

MEDIUM

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 25

How does speed of sound change with change in density of medium?

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 26

Give reason for the following
A sheet of paper falls slower than when it is crumpled into a ball.

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 26

Give reason for the following 
A body weighs more at the poles than at equator.

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 26

Distinguish between mass and weight.

EASY

9th CBSE

IMPORTANT

Together with Science Class 9>Chapter 19 - Practice Paper 4>4; PRACTICE PAPER>Q 27

What are lysosomes, peroxisomes and centrosomes? Write their functions.