Answer: W.D = 1/2mv^2
Explanation:
If an external force or a single force is acting on a body. Just like the first law of thermodynamics, the force acting on the body will cause work done on the system.
Work done = force × distance
And the work done on the body will cause the molecules of the body to experience motion and thereby producing kinetic energy.
The work done will be converted to kinetic energy.
W.D = 1/2mv^2
If net external force acting on the system is zero, momentum is conserved. That means, initial and final momentum are same → total momentum of the system is zero.
The answer is “ The medium”
Answer:

Explanation:
As we know that the level of intensity is given as

here we know



now the sound is travelling in all possible directions so we have



now for level of sound we have


Here's the rule you need to know
in order to answer this question:
1 full circle ==> 360 degrees .
Got that ?
Now you could set up a proportion:
(30 degrees) / (0.01 second) = (360 degrees) / (time for full period)
Cross-multiply the proportion:
(30°) · (period) = (360°) · (0.01 sec)
Divide each side by (30°) : Period = (360° · 0.01 sec) / (30°)
= (3.6° · sec) / (30°)
= (3.6 / 30) sec
= 0.12 sec .
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Another way to look at it:
30° takes 0.01 second
60° takes 0.02 second
90° takes 0.03 second
120° takes 0.04 second
150° takes 0.05 second
180° takes 0.06 second
210° takes 0.07 second
240° takes 0.08 second
270° takes 0.09 second
300° takes 0.10 second
330° takes 0.11 second
360° takes 0.12 second