Answer:
A) Propagation of pressure fluctuations in a medium
B) air is the medium in which the wave is transported,
Explanation:
Part A.
A sound wave is a longitudinal oscillation of the molecules that forms in a material medium, they can be solid, liquid or gases, therefore the wave propagates in the same direction as the oscillation of the particles.
The most correct answer is:
* Propagation of pressure fluctuations in a medium
Part b
air is the medium in which the wave is transported, otherwise it cannot propagate
According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.
Answer:
Let R1= resistance of 4ohms
R2= resistance of 8ohms
Equivalent resistance R will be
R=R1 + R2
=> 4+8=12ohms
The current through the two resistors will be the same since they are connected in series. Notwithstanding, the voltage will drop to appreciate the change.
Explanation:
To solve this problem we will use the concepts related to power, defined as the amount of energy applied over a period of time.
The energy in this case is the accumulated in the form of potential energy, over a period of time. Thus we will have that the mathematical expression of the power can be expressed as

Here,
E = Energy
t = time
As the energy is equal to the potential Energy we have tat

The weight (mg) of the man is 700N, the height (h) is 8m and the time is 10s, then:


Therefore the correct answer is A.
111.0 because 111.009 rounds off to 111.01, thus rounding again off to 111.0