Answer:
The answer is D.
Explanation:
One explanation I can give you is that generally waves travel faster through denser medium because the particles are tightly packed together and so they can transfer energy faster. But to verify the answer, I used Process of Elimination because the other 3 answers are not true. Choice A is entirely true, wave speed depends on the medium it is travelling through, so there is no way choice A is correct. Choice B is wrong because for example if we take light(an EM wave), it travels at a constant speed of 3.0x10^8 m/s in a vacuum and in open space. So, that proves that air or vacuum do not affect the speed of the wave in another medium. Choice C is related to Choice B, we just proved the speed of light is constant everywhere whereas choice C says that in a vacuum the speed is halved. Good luck in your Physics class and I hope for your best!
Answer:
5.3 x 10⁻⁹ C
Explanation:
r = radius of cylindrical shell = 10⁻⁵ m
L = length = 0.32 m
A = area
Area is given as
A = 2πrL
A = 2 (3.14) (10⁻⁵) (0.32)
A = 20.096 x 10⁻⁶ m²
d = separation = 10⁻⁸ m
= dielectric constant = 4
Capacitance is given as
eq-1
V = Potential difference across the membrane = 74 mV = 0.074 Volts
Q = magnitude of charge on each side
Magnitude of charge on each side is given as
Q = CV
using eq-1
Inserting the values
Q = 5.3 x 10⁻⁹ C
By definition, Variable is "(of a quantity) able to assume different numerical values." By this, an example is 4x, as x is an unknown number, but has a value.
Constants are one constant value, unlike Variables.
Distance=20m
time=18s
Initial velocity=0m/s
Final velocity=10m/s
The equation we use to find average velocity is v=d/t (average velocity=distance/time)
V=20m/18s
V (average velocity)=1.11m/s
