Answer:
A.
B.
C.
Explanation:
The capacitance of a capacitor is its ability to store charges. For parallel-plate capacitors, this ability depends the material between the plates, the common plate area and the plate separation. The relationship is
is the capacitance, is the common plate area, is the plate separation and is the permittivity of the material between the plates.
For air or free space, is called the permittivity of free space. In general, where is the relative permittivity or dielectric constant of the material between the plates. It is a factor that determines the strength of the material compared to air. In fact, for air or vacuum, .
The energy stored in a capacitor is the average of the product of its charge and voltage.
Its charge, , is related to its capacitance by (this is the electrical definition of capacitance, a ratio of the charge to its voltage; the previous formula is the geometric definition). Substituting this in the formula for ,
A. Substituting for in ,
B. When the distance is ,
C. When the distance is restored but with a dielectric material of dielectric constant, , inserted, we have
Answer:
The moment of inertia decreased by a factor of 4
Explanation:
Given;
initial angular velocity of the ice skater, ω₁ = 2.5 rev/s
final angular velocity of the ice skater, ω₂ = 10.0 rev/s
During this process we assume that angular momentum is conserved;
I₁ω₁ = I₂ω₂
Where;
I₁ is the initial moment of inertia
I₂ is the final moment of inertia
Therefore, the moment of inertia decreased by a factor of 4
Answer:
36 kg
Explanation:
To answer this question, a few assumptions have to be made:
- That the temperature on the day is 35 °C
- That all the heat from the elephant is goes to warming/evaporating the water on the surface of the elephant
Energy released per hour = 2500 J/s * 3600 s = 9 000 000 J
Q = mcΔT
9 000 000 J= m *4.186 J/g-K * (373K - 308K) + m*2260 J/g
m = 36 000 g = 36 kg