Answer:
best explanation of this is sentence B
Explanation:
The radiation emission of the bodies is given by the expression
P = σ A e T⁴
Where P is the power emitted in watts, σ is the Stefan-Boltzmann constant, A is the surface area of the body, e is the emissivity for black body e = 1 and T is the absolute body temperature in degrees Kelvin.
When the values are substituted the power is quite high 2.5 KW, but the medium surrounding the box also emits radiation
T box ≈ T room
P box ≈ P room
As the two powers are similar and the box can absorbed, since it has the ability to emit and absorb radiation, as the medium is also close of the temperature of the box, the amount emitted is very similar to that absorbed, so the net change in energy is very small.
In the case that the box is much hotter or colder than the surrounding medium if there is a significant net transfer.
Consequently, the best explanation of this is sentence B
The Coulomb force is equal to the constant k times the product of charge one and charge two over radius.
F=k((q1q2)/r)
Answer:
n = 2.06 moles
Explanation:
The absolute pressure at depth of 27 inches can be calculated by:
Pressure = Pressure read + Zero Gauge pressure
Zero Gauge pressure = 14.7 psi
Pressure read = 480 psi
Total pressure = 480 psi + 14.7 psi = 494.7 psi
P (psi) = 1/14.696 P(atm)
So, Pressure = 33.66 atm
Temperature = 25°C
The conversion of T( °C) to T(K) is shown below:
T(K) = T( °C) + 273.15
So,
T = (25 + 273.15) K = 298.15 K
T = 298.15 K
Volume = 1.50 L
Using ideal gas equation as:
PV=nRT
where,
P is the pressure
V is the volume
n is the number of moles
T is the temperature
R is Gas constant having value = 0.0821 L.atm/K.mol
Applying the equation as:
33.66 atm × 1.50 L = n × 0.0821 L.atm/K.mol × 298.15 K
⇒n = 2.06 moles
Answer:v=2 m/s
Explanation:
Given
Length of string L=1.2 m
mass of pendulum m=0.25 kg
maximum inclination with vertical \theta =34
vertical Rise of Pendulum from its mean position is given by

Conserving Energy at top and bottom point
Potential Energy of sphere is converted into kinetic energy of sphere





Answer:
12 N/cm²
Explanation:
From the question given above, the following data were obtained:
Weight (W) of block = 240 N
Area (A) = 20 cm²
Pressure (P) =?
Next, we shall determine the force exerted by the block. This can be obtained as follow:
Weight (W) of block = 240 N
Force (F) =.?
Weight and force has the same unit of measurement. Thus, we force applied is equivalent to the weight of the block. Thus,
Force (F) = Weight (W) of block = 240 N
Force (F) = 240 N
Finally, we shall determine the pressure on the floor as follow:
Force (F) = 240 N
Area (A) = 20 cm²
Pressure (P) =?
P = F/A
P = 240 / 20
P = 12 N/cm²
Therefore, the pressure on the floor is 12 N/cm².