<h2>Answer:</h2><h3>(A) the positively charged surface increases and the energy stored in the capacitor increases.</h3>
When charging a capacitor transferring charge from one surface to the other, the first surface becomes negatively charged while the second surface becomes positively charged. As you transfer the charge, the voltage of the positively charged surface increases and the energy stored in the capacitor also increases. We can solve this by the definition of <em>capacitance</em><em> </em>that is <em>a measure of the ability of a capacitor to store energy. </em>For any capacitor, the capacitance is a constant defined as:
To maintain 
constant, if Q increases V also increases.
On the other hand, the potential energy 
can be expressed as:
In conclusion, as Q increases the potential energy also increases.
Answer:
Energy transition therefore occurs due to the amount of kinetic energy gained by the electrons. The electrons with higher kinetic energy are excited to the higher level (excited state) compare to the electron with low kinetic energy (this energy are energy in the ground state)
Explanation:
Energy level transition occur when light rays strikes a metal surface to emit electron from the surface, a term known as photoelectric effect. This amount of electron emitted from the surface depends on the speed of light ray striking the metal surface.
Energy transition therefore occurs due to the amount of kinetic energy gained by the electrons. The electrons with higher kinetic energy are excited to the higher level (excited state) compare to the electron with low kinetic energy (this energy are energy in the ground state)
Answer:
Radio waves have a wavelength between 
and 
While,
X rays have a wavelength between 1m and 10km.
=> It is one of the condition of diffraction that the obstacle (coming in the way) must be comparable with the size of the wavelength.
=> This shows, that radio waves have a wavelength which is comparable with the size of buildings and can really easily diffract through it
=> While, X-rays are big enough to diffract through the wall.
So, if an X-ray technician stands behind a wall during the use of her machine, she will remain safe.
Answer:
Available energy = 35 x 10⁶ J
Explanation:
Given:
Amount of energy (Q) = 21 gj = 21 x 10⁹ J
Temperature T1 = 600 k
Temperature T0 = 27 + 273 = 300k
Find:
Available energy
Computation:
Available energy = Q[1/T0 - 1/T1]
Available energy = 21 x 10⁹ J[1/300 - 1/600]
Available energy = 35 x 10⁶ J
Answer:
40 N/m
Explanation:
The diagram attached is used to answer the question
We know from Hooke's law that extension is directly proportional to the applied force hence
F=kx where x is extension, F is applied force and k is the spring constant. Making k the subject of the formula then
From the attached diagram extension is given by subtracting unstretched spring from stretched spring hence extension, x=1-0.5=0.5m
Substituting 20 N for F and 0.5 m for x then
