Concept:
Frequency- It is defined as the number of oscillations occur in one second.
Its SI unit is Hertz (Hz)
Given: Produced sound vibrations is 18,500 cycles in 0.75 seconds
∵ In 0.75 second, produced sound has oscillations = 18,500 cycles
∴ In 1.0 second, produced sound has oscillations = (18,500 ÷ 0.75) Hz
The frequency of the sound will be ≈ 24,667 Hz
From the study of the given graph, only the animals (c) Cats, (b) Moths and (a) Bats can hear the produced sound because their upper audible frequency range is greater than 24,667 Hz.

Each increase in the prefix is a division by 1000.
<span>sound waves are a type of wave sometimes called compression waves, vibrations with enough of an amplitude can compress and decompress the air adjacent to the object causing the waves to form.</span>
Both of them are magnets coiled by wires.
1. The wire coiled in the first diagram, the wire is having current, Making the magnetic feild of the magnet more........
2. The wire coiling the magnet is here not having electric current making the magnetic feild smaller
Answer:
Explanation:
Distance travelled = 600 - 500 = 100 m
Time taken = 9:03:25 a.m.- 9:03 :05 a.m.
= 20 s
average speed = distance / time taken
= 100 / 20 m /s
= 5 m /s