<h2>The intensity of siren is 0.015 W m⁻²</h2>
Explanation:
The intensity of sound is inversely proportional to the square of distance between source and the observer .
Thus Intensity at a distance 25 m is I₁ ∝ 
I
Similarly the intensity at a distance 50 m is I₂ ∝ 
II
Dividing II by I , we have
= 
= 
= 
Thus I₂ = x 0.06 = 0.015 W m⁻²
I don't think an object can exert a force on itself.
Try it: Get up on a skateboard, and see if you can do anything to yourself that makes you start moving ... without touching anything else.
It'll be easy to tell if you succeed. If you actually do exert an unbalanced force on yourself, then you'll begin to accelerate.
Answer:
B. The water
Explanation:
Water is abiotic factor because it is non living
Answer:
V = 2.87 m/s
Explanation:
The minimum speed required would be that at which the acceleration due to gravity is negated by the centrifugal force on the water.
Thus, we simply need to set the centripetal acceleration equal to gravity and solve for the speed V using the following equation:
Centripetal acceleration = V^2 / r
where r is the distance of water from the pivot or shoulder.
For our case, r will be 0.65 + 0.19 = 0.84 m
and solving the above equation we get:
9.81 = V^2 / 0.84
V^2 = 8.2404
V = 2.87 m/s
