Answer:
By a factor 9
Explanation:
The intensity of a sound wave is proportional to the square of the amplitude of the wave:

where
I is the intensity
A is the amplitude of the wave
In this problem, the amplitude of the sound wave is increased by a factor 3:
A' = 3A
So the intensity would change by

So, the intensity would increase by a factor 9.
Answer:
electric
<em>please give brainliest</em>
Answer:
2 m/s
Explanation:
Parameters given:
Mass of first skateboard, m = 3 kg
Initial speed of first skateboard, u = 4 m/s
Mass of second skateboard, M = 1 kg
Initial speed of second skateboard, U = 0 m/s
Final speed of second skateboard, V = 6 m/s
Using the principle of the conservaton of momentum, the total initial momentum is equal to the total final momentum.
Momentum is the product of mass and velocity. This implies that:
m*u + M*U = m*v + M*V
(3*4) + (1*0) = (3*v) + (1*6)
12 + 0 = 3v + 6
=> 3v = 12 - 6
3v = 6
v = 6/3 = 2 m/s
The final speed of the 3 kg skateboard is 2 m/s