Answer:
97.03%
Explanation:
The equation for volumetric expansion due to thermal expansion is as follows
V/Vo=(1+γΔT)
V=final volume
Vo=initial volume
γ=coefficient of volume expansion=3.2 × 10–5 K–1
ΔT=
temperature difference
assuming that the earth is a sphere the volume is given by
V=(4/3)pi R^3
if we find the relationship between the initial and final volume we have the following
taking into account the previous equation
r/ro=(1+γΔT)^(1/3)
r/r0=(1-3.2x10-5(3000-300))^(1/3)=
r/ro=0.9703=97.03%
Not sure the precise concept of "normal observation", but I assume that is observed by "eyes".
Eye observation is basically macroscopic, but when you use a mark, which can be regarded as a point of mass, then it goes to microscopic.
Mark is a reference point which you can compare the relative position change, but with your eyes, first you cannot notice microscopic changes, second the eyes cannot precisely set a stable reference point.
This phenomenon is as a result of static friction created by the tumbling clothes. Static friction results from the rubbing together of two or mores objects or body and electrons are stripped from one surface of the clothes more than the other. This creates an electrostatic force of attractions between the positive charges on one cloth and the negative charges on the other cloth.(unlike charges attract).
C.) Laser. the light from the laser reflects off the shiny surface as the CD rotates
