Answer:
The air-water interface is an example of<em> </em>boundary. The <u><em>transmitted</em></u><em> </em> portion of the initial wave energy is way smaller than the <u><em>reflected</em></u><em> </em> portion. This makes the <u><em>boundary</em></u> wave hard to hear.
When both the source of the sound and your ears are located underwater, the sound is louder because the sound waves can <u><em>travel directly to your ear</em></u>.
Explanation:
The air-to-water sound wave transmission is inhibited because more of reflection than transmission of the wave occurs at the boundary. In the end, only about 30% of the sound wave eventually reaches underwater. For sound generated underwater, all the wave energy is transmitted directly to the observer. Sound wave travel faster in water than in air because, the molecules of water are more densely packed together, and hence can easily transmit their vibration to their neighboring molecules, when compared to air.
Answer:
This point is not accelerating.
Explanation:
An object can be acted on by several forces at the same time, these forces are vector quantities (with magnitude and direction associated). The vector sum of all of the forces acting on a body is a single force called the net force when an object is in equilibrium this net force is equal to zero.
<em>According to Newton's second law of motion, the acceleration of an object as produced by a net force is directly proportional to the net's force, direction, and force and inversely proportional to the mass of the object. </em><em>This means that if the net force is zero an object will have zero acceleration.</em>
Therefore we can conclude that the sum of the three forces acting on the center point of the rope is assumed to be zero this point is not accelerating.
I hope you find this information useful and interesting! Good luck!
Pretty sure it's the last one:
"reduce the size of the input force needed to perform a task"
Answer:
3.90 degrees
Explanation:
Let g= 9.81 m/s2. The gravity of the 30kg grocery cart is
W = mg = 30*9.81 = 294.3 N
This gravity is split into 2 components on the ramp, 1 parallel and the other perpendicular to the ramp.
We can calculate the parallel one since it's the one that affects the force required to push up
F = WsinΘ
Since customer would not complain if the force is no more than 20N
F = 20
So the ramp cannot be larger than 3.9 degrees
Answer:
Velocity
Explanation:
The gradient= change in velocity
——————————
Change in time
