Given Information:
Diameter of spherical cell = 0.040 mm
thickness = L = 9 nm
Resistivity = ρ = 3.6×10⁷ Ω⋅m
Dielectric constant = k = 9.0
Required Information:
time constant = τ = ?
Answer:
time constant = 2.87×10⁻³ seconds
Explanation:
The time constant is given by
τ = RC
Where R is the resistance and C is the capacitance.
We know that resistivity of of any material is given by
ρ = RA/L
R = ρL/A
Where area of spherical cell is given by
A = 4πr²
A = 4π(d/2)²
A = 4π(0.040×10⁻³/2)²
A = 5.026×10⁻⁹ m²
The resistance becomes
R = (3.6×10⁷*9×10⁻⁹)/5.026×10⁻⁹
R = 6.45×10⁷ Ω
The capacitance of the cell membrane is given by
C = kεoA/L
Where k = 9 is the dielectric constant and εo = 8.854×10⁻¹² F/m
C = (9*8.854×10⁻¹²*5.026×10⁻⁹)/9×10⁻⁹
C = 44.5 pF
C = 44.5×10⁻¹² F
Therefore, the time constant is
τ = RC
τ = 6.45×10⁷*44.5×10⁻¹²
τ = 2.87×10⁻³ seconds
Answer:
The heat of vaporization 580 cal/g times 602g = cal in human and do the same for life form.
Explanation:
Answer:
Rate of change of magnetic field is
Explanation:
We have given diameter of the circular loop is 13 cm = 0.13 m
So radius of the circular loop 
Length of the circular loop 
Wire is made up of diameter of 2.6 mm
So radius 
Cross sectional area of wire 
Resistivity of wire 
Resistance of wire 
Current is given i = 11 A
So emf 
Emf induced in the coil is 


Answer:
The side the boy is sitting on will tilt downward.
Explanation:
According to the law of moments when the same force is applied at a greater distance from the pivot then the effect of moment is greater about that point.
<u>Mathematically momentum is given as:</u>

where:
F is the applied force at a distance 'r' acting in a direction perpendicular to the line joining the point of application and the hinge.
- Moment is the rotational effect of the applied force on the body.
<em>When the boy of a heavier mass than the girl was sitting on a balanced see-saw then it is certain that he was closer to the hinge than the girl to balance the turning effect (in case of an unbiased see-saw). When the body moves farther his weight is same but the radial distance from the hinge increases which increases his moment of weight.</em>
25/1500 is equal to 0.8/x
0.8*1500 is equal to 1200
1200/25 is equal to 48 N