Answer:
4.80 seconds
Explanation:
The velocity of sound is obtained from;
V= 2d/t
Where;
V= velocity of sound = 329.2 ms-1
d= distance from the wall = 790.5 m
t= time = the unknown
t= 2d/V
t= 2 × 790.5/ 329.2
t= 4.80 seconds
In that case, their momentum must be equal.
So, m1v1 = m2v2
20 * 20 = 40 * v2
v2 = 400 / 40
v2 = 10
In short, Your Answer would be: 10 m/s
Hope this helps!
Answer:
time=4s
Explanation:
we know that in a RL circuit with a resistance R, an inductance L and a battery of emf E, the current (i) will vary in following fashion
, where
max=
Given that, at i(2)=
⇒
⇒
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Applying logarithm on both sides,
⇒
⇒
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Now substitute 
⇒
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⇒
Applying logarithm on both sides,
⇒
⇒
⇒
now subs. 
⇒
also 
⇒
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