Answer:
Ratio of length will be 
Explanation:
We have given time period of the pendulum when length is 
is 
And when length is 
time period 
We know that time period is given by
So 
----eqn 1
And 
-------eqn 2
Dividing eqn 2 by eqn 1
Squaring both side
Whenever lightning strikes it separates the air where it goes. This air then rushes back together making a loud noise when it connects, creating thunder.
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Answer: 7.41 m/s
Explanation: By using the law of of energy, kinetic energy of the brick as it falls equals the potential energy before falling.
Kinetic energy = mv²/2, potential energy = mgh
mv²/2 = mgh
v²/2 = gh
v² = 2gh
v = √2gh
Where g = 9.8 m/s², h = 2.80m
v = √2×9.8×2.8 = 7.41 m/s
<span>Tectonic plates move because they are floating on top of the liquid mantle. The mantle itself moves due to convection currents: hot rock rises, gives off some heat, then falls. This creates vast swirls of moving liquid rock under the crust of the earth, which jostles the plates of crust on top.
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