Answer:
option D
Explanation:
given,

increase the intensity by factor of 9
I₁ = I₀
I₂ = 9 I₀
now,




A₂ = 3 A₁
hence, amplitude increase with the factor of 3
so, the correct answer is option D
The value of g at sea level is 9.81 ms^-2.
The boy's mass is constant wherever he is in the universe but his weight will depend on the strength gravity where he is.
By proportion its value on the mountain peak is (360 /400) * 9.81
= 0.9 * 9.81 = 8.83 ms^-2 to nearest hundredth, (answer).
The final speed of an airplane is v = 92.95 m/s
The rate of change of position of an object in any direction is known as speed i.e. in other word, Speed is measured as the ratio of distance to the time in which the distance was covered.
Solution-
Here given,
Acceleration a= 10.8 m/s2 .
Displacement (s)= 400m
Then to find final speed of airplane v=?
Therefore from equation of motion can be written as,
v²=u²+ 2as
where, u is initial speed, v is final speed ,a is acceleration and s is displacement of the airplane. Therefore by putting the value of a & s in above equation and (u =0) i.e. the initial speed of airplane is zero.
v²= 2×10.8 m/s²×400m
v²=8640m/s
v=92.95m/s
hence the final speed of airplane v =92.95m/s
To know more about speed
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