Answer:
9R
Explanation:
We know that the resistance is 
.
If we stretch the wire to a new length L2 = 3L, the cross-sectional area will also change. If the cross-sectional area doesn't change throughout the wire, we can say that:
Volume = L*A = 3L * A2 being A2 the new area after stretching the wire.
Since the volume remains the same we conclude that A2 = A/3
With this information, we calculate the new resistance:
Since , and by simple inspection of the previous equation, we get:
<em>R2 = 9*R</em>
Answer: machine's efficiency = 82.2%
Explanation:
Efficiency of a machine is the capability of a machine to convert input to output without waste.
It can be expressed as
Efficiency = output/ input × 100%
Output = 7,023N
Imput = 8,542N
Efficiency = 7,023N/8,542N × 100%
Efficiency = 82.2%
The gravitational force between a mass and the Earth is the object'sweight. Mass is considered a measure of an object's inertia, and its weight is the force exerted on the object in a gravitational field. On the surface of the Earth, the two forces are related by the acceleration due to gravity: Fg = mg.
Hoped this helped!
Answer:
D. are brought from the mantle to the surface in magma that hardens into komatiite.
Explanation:
Diamond :
It is the hardest form of carbon.The atomic atoms arrange in the cubic crystal structure and this is known as diamond cubic.Another form of the diamond at room temperature is graphite.This is used for making jewelry.This is also used in the cutting process because it has high strength.
Therefore the correct option for the diamond is D.
Nuclear energy <em>is t</em><span><em>he energy released during nuclear fission or fusion.
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