Seeing With Sound
Written by Studio AM.
Your result
- Words per minute
- Score
- Pace
Words per minute mean something only with the score beside them. They describe this passage on this read. With fewer than 3 right, try the next slower pace.
Choose a pace and select Start. The passage is paced and timed, then the questions check what you understood. How pace mode works
Reading time 0:00
Many insect-eating bats can hunt in darkness by listening to echoes. They also have eyesight, which can provide information when light is available. They manage this by using sound the way we use light. As a bat flies, it sends out a stream of high, sharp calls, most of them too high for human ears to hear.
When a call strikes an object, part of the sound bounces back as an echo. The bat listens for these returning echoes and reads them closely. A nearer object sends its echo back sooner, so the delay tells the bat how far away something is. Changes in the echo hint at the object's size and even the direction it is moving. From a rapid stream of echoes, the bat builds a picture of the space around it.
This method is called echolocation: finding the location of things by their echoes. It is so precise that a bat can catch a single insect in midair or weave through branches it cannot see. Where our eyes fail in the dark, echolocation lets a bat use sound to locate nearby objects.
The passage is hidden while you answer. It comes back with your result.
Questions
Choose an answer. The explanation appears after you answer.
-
Question 1 of 4
The passage mainly explains
The answer is D: how bats find things by echo
The passage explains echolocation: how bats read echoes to sense their surroundings in the dark.
-
Question 2 of 4
What does the delay of an echo tell the bat?
The answer is B: How far away the object is
The text says a nearer object echoes back sooner, so 'the delay tells the bat how far away something is'.
-
Question 3 of 4
Why can bats hunt where our eyes fail?
The answer is B: They use echoes, which do not need light
Echoes do not require light, so they can provide information when vision is limited by darkness.
-
Question 4 of 4
In this passage, 'echolocation' means
The answer is B: finding where things are by their echoes
The text defines it: 'finding the location of things by their echoes'.
Score: none answered yet.