Length of the copper rod = 2.5 meters
Speed at which sound travels through copper = 3560 meter per second
Let us assume the time taken
by sound to cover the given distance = x seconds
We already know that
Speed = Distance/ Time
Then
Time = Distance/ Speed
x = 2.5/3560 seconds
= 0.0007 seconds.
This can ve done by hitting one end of the rod and then receiving the sound at the other end and using the stop clock to measure the time taken.
B)
If it is known that the atomic number is 8, we know that the electrons are also 8. Since the atomic mass (O18) is 18, the neutrons are 18-8=10. Option B is the correct answer.
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Planet A is heavier than Planet B
Because Planet A is heavier than Planet B, Planet B will be easier to be moved by gravity causing it to move faster than Planet A.
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