6. Drop to one quarter of its original value
Answer:

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%
Explanation:
From the exercise we know two information. The real speed and the experimental measured by the speedometer

Since the speedometer is only accurate to within 0.1km/h the experimental speed is

Knowing that we can calculate Kinetic energy for the real and experimental speed


Now, the potential error in her calculated kinetic energy is:

%
%
Answer:
The Flemings left hand rule is used to find the magnitude of a magnetic force
Explanation:
Fleming's left hand rule states that if the first three fingers are held mutually at right angles to one another, then the fore finger points into the direction of magnetic field the middle finger in the direction of current while the thumb points in the direction of force.
Mathematically
Magnetic Force F= BILsinθ
Where
B= magnetic field density Tesla
I= current
L= length of conductor
θ= angle of conductor with field
The fact that the layers of graphite are held together by only weak Van der Walls forces implies that they can slide over each other.
<h3>Why is graphite a solid lubricant?</h3>
We know that graphite is composed of layers. These hexagonal layers are held together by weak Van Der Walls forces and as such are able to slide over each other. The carbon atom in each layer are held together by strong covalent bonds.
The fact that the layers of graphite are held together by only weak Van der Walls forces implies that they can slide over each other and as such make the graphite fluid.
Thus, the image that shows these layers of graphite is attached to this an answer
Learn more about graphite:brainly.com/question/11095487
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