1) c. 2 m/s
Explanation:
The relationship between frequency, wavelength and speed of a wave is
where
v is the speed
is the wavelength
f is the frequency
For the wave in this problem,
f = 4 Hz
So, the speed is
2) a. 2.8 m/s
The speed of the wave on a string is given
where
T is the tension in the string
is the linear mass density
In this problem, we have:
(final tension in the rope, which is twice the initial tension)
--> mass density of the rope
Substituting into the formula, we find
The equation that would allow us to calculate for the acceleration given the distance is written below,
a = (Vf² - Vo²) / 2d
where a is the acceleration, Vf is the final velocity, Vo is the initial velocity, and d is distance.
Substituting the known values,
a = ((84 ft/s)² - (72 ft/s)²) / 2(180 ft) = 5.2 ft/s²
Then, the equation that would relate the initial velocity, distance, acceleration and time is calculated through the equation,
d = Vot + 0.5at²
Substituting the known values,
180 = 72(t) + 0.5(5.2)(t²)
The value of t from the equation is 2.3 s
<em>ANSWER: 2.3 s</em>
The law of conservation of energy states that energy is neither created nor destroyed; the amount remains constant. For example, a form of energy-thermal energy, or heat, occurs by convection or conduction
Answer:
The answer is below
Explanation:
Because of the resistance of transmission lines, high current along the line leads to large voltage drop. This voltage drop causes low efficiency because the voltage at the receiving end is far less than that at the sending end.
Therefore there is need to transmit at a higher voltage (smaller current) than that required by distribution because of efficiency.
Hence, For safety and efficiency, the voltage must be large in the transmission lines and small in the distribution lines.
