Answer:
Thermal Power = 460W
Explanation:
From Stephan-Boltzmann Law Formula;
P = єσT⁴A
Where,
P = Radiation energy
σ = Stefan-Boltzmann Constant
T = absolute temperature in Kelvin
є = Emissivity of the material.
A=Area of the emitting body
Now, σ = 5.67 x 10^(-8)
є = 0.6
Temperature = 30°C and coverting to kelvin = 30 + 273 = 303K
Area ; since we are to consider the sides of the human body as 2m and 0.8m,thus area = 2 x 0.8 = 1.6
Thus thermal power = 0.6 x 5.67 x 10^(-8) x303⁴ x 1.6 = 458. 8W
Normally, we approximate to the nearest 10W. Thus, thermal power is approximately 460W
Answer:
Options A and B.
Explanation:
Gravitational acceleration, initial height, intial speed and time are required to determine final speed. The option D is incorrect, since speed varies in time. Option C is dimentionally wrong.
The correct strategy is calculating the initial height from option B. Later, substituting time in equation A to derive an expression of the final velocity in terms of position. Hence, the required equations are options A and B.
Answer:
The electric force will be 0 N
Explanation:
From the question we are told that
The magnitude of the charge is 
Generally from Coulombs law the electric force between two charges is mathematically represented as

Here r is the distance of separation between that two charges.
Now from the question we are told that the charge is far away from any other charge hence we can say that the distance between the charge and any other charge is 
So

=> 
Hence the electric force will be 0 N