Answer:
The expresion for the flux through the disk is:
Ф = E·πR^2·cos(Θ).
Explanation:
Let's sat the electric field has direction e and the normal to the disk has direction n (bold means vector quantities). So we have:
E=E·e (where E is the magnitud of the electric flied)
A=A·n
The flux for an uniform electric field and a flat surface is:
Ф=E×A
⇒ Ф = E·A·e×n = E·A·cos(angle(e,n)) = E·A·cos(Θ)
Since in this case the area is for a disk of radius R, 
So, Ф = E·πR^2·cos(Θ)
Question: Which of the following is true about scientific models? Select one: A) Models are used to simplify the study of things. B) Computer models are the most reliable kind of model. C) Models explain past, present and future information. D) A model is accurate if it does not change over time.
Answer: <u>A) Models are used to simplify the study of things.</u>
<em>Hope this helps!.</em>
<em>~~~~~~~~~~~~~~~~~~~~~~</em>
<em>~A.W~ZoomZoom44</em>
According to Coulomb's Law , The size of the force varies inversely as the square of the distance between the two charges. So ,if the distance between the two charges is doubled, the electrostatic force will become weak by one fourth of the original force.
When a star is moving away from earth it appears blue
Answer:
(a) m = 1.6 x 10²¹ kg
(b) K.E = 2.536 x 10¹¹ J
(c) v = 7.12 x 10⁵ m/s
Explanation:
(a)
First we find the volume of the continent:
V = L*W*H
where,
V = Volume of Slab = ?
L = Length of Slab = 4450 km = 4.45 x 10⁶ m
W = Width of Slab = 4450 km = 4.45 x 10⁶ m
H = Height of Slab = 31 km = 3.1 x 10⁴ m
Therefore,
V = (4.45 x 10⁶ m)(4.45 x 10⁶ m)(3.1 x 10⁴ m)
V = 6.138 x 10¹⁷ m³
Now, we find the mass:
m = density*V
m = (2620 kg/m³)(6.138 x 10¹⁷ m³)
<u>m = 1.6 x 10²¹ kg</u>
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(b)
The kinetic energy will be:
K.E = (1/2)mv²
where,
v = speed = (1 cm/year)(0.01 m/1 cm)(1 year/365 days)(1 day/24 h)(1 h/3600 s)
v = 3.17 x 10⁻¹⁰ m/s
Therefore,
K.E = (1/2)(1.6 x 10²¹ kg)(3.17 x 10⁻¹⁰ m/s)²
<u>K.E = 2.536 x 10¹¹ J</u>
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(c)
For the same kinetic energy but mass = 77 kg:
K.E = (1/2)mv²
2.536 x 10¹¹ J = (1/2)(77 kg)v²
v = √(2)(2.536 x 10¹¹ J)
<u>v = 7.12 x 10⁵ m/s</u>
