Answer
given,
Hunk Finn speed,v_y= 0.7 m/s
Speed of river,v_x = 1.50 m/s
Assuming the speed of the river is in x-direction.
Speed of Hunk Finn to be in y-direction.
Hunk velocity relative to river =
Speed of Hunk relative to river = 1.66 m/s
direction of the boat
Hence, angle of the raft is 24.01°
This is EXACTLY the same scenario as the skydiver jumping
out of the airplane, except the whole thing is turned on its side.
==> The skydiver leaves the airplane.
The force of gravity on him (his weight) makes him accelerate down.
But the air resists his downward motion.
The faster he falls, the more UPWARD force the air exerts on him.
The more upward force the air exerts, the less he accelerates down.
When his falling speed is great enough, he stops accelerating, and
falls with a constant speed. He calls that speed his 'terminal velocity'.
==> The submarine turns on its engines, at maximum power.
The force of the engines makes the sub accelerate forward.
But the water resists its forward motion.
The faster it moves, the more BACKWARD force the water exerts on it.
The more backward force the water exerts, the less it accelerates forward.
When the forward speed is great enough, it stops accelerating, and moves
with a constant speed. I don't know if they use the same term in submarines,
but you might say that speed is the 'terminal velocity' in water.
All except B are examples of force
Sound intensity goes inversely as the square of the distance from the source. This is easy to understand if you think of the total sound energy spread out over the surface of a sphere with the source at the center. The surface area of the sphere goes as r^2, so the power density goes inversely as such.
The decibel change is simply
Change = 10 log10( (1/3)^2 ) = -9.54 dB
Answer:
stabilize
I think this should be the answer...
