Revision topic 2.3 and 3.3

What does "muffling of sound" refer to

• Amplifying the sound
  

• B) Making the sound louder
  

• C) making sound quieter or softer                                    

Which of the following are ways to reduce noise?

• A) Curtains – Thick curtains absorb sound and reduce noise.

• B) Carpet – Carpets help absorb sound and reduce echoes.

• C) Metal Sheets – Metal sheets reflect sound, making noise worse, not muffling it.

• A AND B correct

What happens to the sound level as the distance increases?

• A) The sound level increases
  

• 
  B) The sound level decreases
  

• 
  C) The sound level stays the same

Which of the following is true about dependent variables?

• A) The dependent variable is what you measure in the experiment.
  

• 
  B) The dependent variable is what you change in the experiment.
  

• 
  C) The dependent variable stays the same throughout the experiment.

Which of the following is true about independent variables?

• A) The independent variable is what you measure in the experiment.
  

• 
  B) The independent variable is what you change in the experiment.
  

• 
  C) The independent variable stays the same throughout the experiment.

Jack is trying to increase the volume of sound using a sheet of card. Which of the following will help him hear the sound more clearly by using the card’s shape?

• a) Fold the card into a cone and listen through it.

• b) Roll the card into a tube and listen through it.

• c) Lay the card flat on a table.

Answer explanation

a wider opening at the source and a narrower opening at the ear creates a louder, more focused sound.

What happens when you hit a drum hard?

• A) It makes a louder sound
  

• 
  B) It makes a softer

• 
  C) It makes no sound

1. What is evaporation?

• A) The process of water turning into ice
  

• B) The process of water turning into vapor
  

• 
  C) The process of water becoming solid

2. Which of the following increases the rate of evaporation?

• 
  A) Low temperature
  

• 
  B) High humidity
  

• 
  C) High temperature

4. Which of the following causes faster evaporation?

• A) Wind
  

• 
  B) Cold weather
  

• 
  C) A sealed container