<span>Birds sitting on a single power line don't get shocked because there is no path for the current to flow to the "ground."</span>
Answer:
-14.2m/s
Explanation:
Given parameters:
Initial velocity of the ball = 25m/s
Time = 4s
Unknown:
Final velocity of the ball = ?
Solution:
To solve this problem, we use the expression below;
v = u - gt
v is the final velocity
u is the initial velocity
g is the acceleration due to gravity
t is the time
v = 25 - (9.8 x 4) = -14.2m/s
Echo means repetition of sound..If someone is speaking there will be two sounds..one which he is speaking right now and the other sound which he/she spoke earlier ..this will lead to confusion..in big halls the distance would be more than 17 m between the walls which will cause echo and not reverberation(prolongation of sound)
Hope this helps!
Answer: Solid
Explanation: Most of the outer part of our planet is solid. This solid mantle sits on an outer liquid core and a solid inner core.
<span>(A)
s{ t } = (¼)t² + 2t + 1 ... differentiate to get velocity versus time
v{ t } = (½)t + 2 ... linearly increases with time
(1)
Vavɢ{ a→b } = [ v{ b } + v{ a } ] ⁄ 2
Vavɢ{ 1→3 } = [ v{ 3 } + v{1 } ] ⁄ 2
Vavɢ{ 1→3 } = [ (½)(3) + 2 + (½)(1) + 2 ] ⁄ 2
Vavɢ{ 1→3 } = 3 m/sec
(II) and (III) are done the same way.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...
(B)
v{ t } = (½)t + 2
v{1 } = (½)(1) + 2
v{1 } = 2.5 m/sec</span>