Answer:
13.98 nC
Explanation:
Capacitance depends upon the area of the plates and their distance of separation.
Radius = r = 0.071 m
separation = d = 0.00126 m
here κ = 1 and ε₀ = 8.85 ₓ 10⁻¹² SI units , for free space.
Area = A = π r² = 0.0158 m²
C = [( 8.85 ₓ 10⁻¹² ) ( 0.0158) ]÷ (0.00126) = 1.11 x 10⁻¹⁰ F
Charge = Q = C V = ( 1.11 x 10⁻¹⁰ F )(126) = 13.98 nC
= 14 nC ( rounded to two significant digits)
Answer:
Explanation:
A Spring stretches / compresses when force is applied on them and they are governed by the Hookes Law which states that the force required to stretch or compress a spring is directly proportional to the distance it is stretched.
F is the force applied and x is the elongation of the spring
k is the spring constant.
negative sign indicates the change in direction from equilibrium position.
In the given question, we dont have force but we know that the pan is hanging. We also know from the Newton's second law of motion that
Inserting this into Hooke's Law
computing it for x,
This is the model which will tell the length of the spring against change in the mass located in the pan.
Answer:
The farther star will appear 4 times fainter than the star that is near to the observer.
Explanation:
Since it is given that the luminosity of the 2 stars is same thus they radiate the same energy per unit time
Consider a spherical wave front of energy 'E' that leaves both the stars (Both radiate 'E' as they have same luminosity)
This Energy is spread over the whole surface area of sphere Thus when the wave front is at a distance 'r' the energy per unit surface area is given by
For the star that is twice away from the earth the distance is '2r' thus we will receive an energy given by
Hence we sense it as 4 times fainter than the nearer star.