<span>When water freezes to form ice, its volume expands. However, we know from conservation of mass that the mass of the ice is the same as the mass of the water. Since density is defined fundamentally as mass / volume, and we have an expanding volume at a constant mass, the denominator of the equation grows, and thus the density of ice is lower than that of liquid water.</span>
Answer:
v = 0.92 c
Explanation:
Here, we will use the time dilation formula from Einstein's theory of relativity to find the speed of traveling of the friend:
where,
v = speed of traveling = ?
c = speed of light
t = time of return = 10 years
t₀ = time passed on earth = 4 years
Therefore,
<u>v = 0.92 c</u>
Answer:
Explanation:
plate separation = 2.3 x 10⁻³ m
capacity C₁ = ε A / d
= ε A / 2.3 x 10⁻³
C₂ = ε A / 1.15 x 10⁻³
= 
a ) when charge remains constant
energy = 
q is charge and C is capacity
energy stored initially E₁= 
energy stored finally E₂ = 
=
= 
= 
= 4.19 J
b )
In this case potential diff remains constant
energy of capacitor = 1/2 C V²
energy is proportional to capacity as V is constant .
= 16.76 .
Answer:
D. The temperature does not change during a phase change because the average kinetic energy does not change. Therefore, the potential energy in the bonds between molecules must change.
Explanation:
When there is a change of state (for example, from solid into a liquid, as in this example), when energy is added to the system, the temperature of the substance does not change.
The reason for this is that the energy supplied is no longer used to increase the average kinetic energy of the particle, but instead it is used to break the bonds between the different particles/molecules. For instance, since in this case the substance is changing from solid to liquid, all the energy supplied during the phase change is used to break the bonds between the molecules of the solid: when the process is done, all the molecules will be free to slide past each other, and the substance has turned completely into a liquid.
The bonds between molecules store potential energy: therefore, this means that the energy supplied during the phase change is not used to change the kinetic energy, but to change the potential energy in the bonds between the molecules.
Inertia- a tendency to do nothing or to remain unchanged
