Answer:
The correct answer is B
An echo underwater and an echo in the air will return at different times. The echo underwater will return more quickly than the echo in the air.
Explanation:
The physics of this is simple.
Water and air are both made up of particles. The particles for water are more closely or densely arranged that those of the air molecules. Hence sound travels faster in water than in air. When measured, the speed actually differs by as much as 5 times with water being the fastest medium.
Think of it like this. Assume you have two stacks of dominoes, one closely packed than the other but exactly the same amount of dominos, you'd notice that the stack that is more tightly arranged will be the first to topple over because it takes less time for the kinetic energy from the first domino to reach the next and on and on like that until the last domino.
Cheers
Idk but it must be hard tho
Answer: 9cm
Explanation:
Refractive index can also be defined as the ratio of the real depth to the apparent depth.
Given that the
Real depth = 12 m
Refractive index of water = 1.33
Refractive index of air = 1.00
nair/nwater = real depth/apparent depth
Substitute all the parameters into the formula
1.33/1 = 12/ apparent depth
Cross multiply
1.33 Apparent depth = 12
Apparent depth = 12/1.33
Apparent depth = 9.02 cm
Therefore, A submerged swimmer in the pool sees the tip of the triangle at 9cm approximately distance above the water.
Answer:
a)27.3N
b)150.78N
Explanation:
Having in mind the conservation of energy, as the monkey goes up (gaining potential gravitational energy) the kinetic energy must be reduced, so reducing the velocity of the monkey. So the maximum velocity will be at this lower point with a velocity of 1.36m/s
From this velocity and the radius we can calculate the angular velocity for the monkey center of mass:

with this we can calculate the centripetal force magnitude:

On the mokey center of mass we have two opposite forces acting, the tension of the arm and the weight, in order for the monkey to continue swinging the resolt of this two forces must be equal to the centripetal force:


Answer:
Explanation:
The y component of the force is 100 sinØ . But given that y component is 30N
so 100 sinØ = 30
sinØ = 0.3
Ø = 17.5°.
X component of force = 100 cosØ
= 100 cos17.5
= 95.35 N .
Y component of force = 30 N .
Angle Ø = 17.5°.