efficiency = (useful energy transferred ÷ energy supplied) × 100
It's easy to use this formula, but we have to know both the useful energy and the energy supplied.  The drawing doesn't tell us the useful energy, so we have to find a clever way to figure it out.  I see two ways to do it:
<u>Way #1:</u>
We all know about the law of conservation of energy.  So we know that the total energy coming out must be  250J, because that's how much energy is going in.  The wasted energy is 75J, so the rest of the 250J must be the useful energy . . . (250J - 75J) = 175J useful energy.
(useful energy) / (energy supplied) =  (175J) / (250J) = <em>70% efficiency</em>
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<u>Way #2: </u>
How much of the energy is wasted ? . . . 75J wasted
What percentage of the Input is that 75J ? . . . 75/250 = 30% wasted
30% of the input energy is wasted.  That leaves the other <em>70%</em> to be useful energy.
 
        
                    
             
        
        
        
Answer:
13807.2  J/g°C
Explanation:
I just took the test and got it correct
 
        
             
        
        
        
Responder:
Explicación:
Usaremos la ecuación de movimiento para determinar la altura de la bola medida desde la parte superior del edificio.
Usando la ecuación para obtener la altura de caída
S = ut + 1 / 2gt²
u es la velocidad inicial = 25 m / s
g es la aceleración debida a la gravedad = 9,81 m / s²
t es el tiempo = 7 segundos
S es la altura de la caída
S = 25 (7) +1/2 (9,81) × 7²
S = 175 + 4,905 (49)
S = 175 + 240,345
S = 415,35 m
Esto significa que la pelota se elevó a 415,35 m de altura
 
        
             
        
        
        
The natural light display called aurora borealis is located in the northern 
hemisphere.
There are two types of aurora which are called aurora borealis and aurora 
australis. The aurora borealis is located in the Northern hemisphere while 
the aurora australis is located in the Southern hemisphere.
They receive their energy through the interaction of charged particles 
on the Sun and Earth to produce the light display. An example 
of the interaction involves solar wind with atoms of the upper atmosphere. 
Read more on brainly.com/question/20191244
 
        
             
        
        
        
Answer:
<em>More current will be loss through the metal wire strands if the force on them was repulsive, and more stress will be induced on the wire strands due to internal and external flexing.</em>
<em />
Explanation:
A wire bundle is made up of wire strands bunched together to increase flexibility that is not always possible in a single solid metal wire conductor. In the strands of wire carrying a high voltage power, each strand carries a certain amount of current, and the current through the strands all travel in the same direction. <em>It is know that for two conductors or wire, separated by a certain distance, that carries current flowing through them in the same direction, an attractive force is produced on these wires, one on the other. This effect is due to the magnetic induction of a current carrying conductor.</em> The forces between these strands of the high voltage wire bundle, pulls the wire strands closer, creating more bond between these wire strands and reducing internal flex induced stresses.
If the case was the opposite, and the wires opposed themselves, the effect would be that a lot of cost will be expended in holding these wire strands together. Also, stress within the strands due to the repulsion, will couple with external stress from the flexing of the wire, resulting in the weakening of the material.
<em>The biggest problem will be that more current will be lost in the wire due to increased surface area caused by the repulsive forces opening spaces between the strand. This loss is a s a result of the 'skin effect' in wire transmission, in which current tends to flow close to the surface of the metal wire. The skin effect generates power loss as heat through the exposed surface area.</em>