Answer:
k = 6.72
Explanation:
K of paper = 3.7
k of air = 1
Given that charge Q on the capacitor is constant because cell is disconnected from the circuit. So
V = Q / C = 2.5
Capacity becomes C / 3.7 in air .
capacity becomes C/3.7 when paper is replaced by air .
V₁ = Q / (C/3.7)
= 3.7 Q/C
3.7 x 2.5
= 9.25 V
In the second case ,
capacitance due to new unknown dielectric k
= C/3.7 x k
= kC / 3.7 ( Capacitance in air is C/3.7 )
V ( new ) = Q / ( kC/3.7 )
= 3.7 Q/kC
.55 x 2.5 = 3.7 x( 2.5 / k )
k = 3.7 / .55
= 6.72
I’m pretty sure it’s, B. An Electric Motor. I apologize in advance if it’s incorrect.
Answer:
Angle θ = 30.82°
Explanation:
From Malus’s law, since the intensity of a wave is proportional to its amplitude squared, the intensity I of the transmitted wave is related to the incident wave by; I = I_o cos²θ
where;
I_o is the intensity of the polarized wave before passing through the filter.
In this question,
I is 0.708 W/m²
While I_o is 0.960 W/m²
Thus, plugging in these values into the equation, we have;
0.708 W/m² = 0.960 W/m² •cos²θ
Thus, cos²θ = 0.708 W/m²/0.960 W/m²
cos²θ = 0.7375
Cos θ = √0.7375
Cos θ = 0.8588
θ = Cos^(-1)0.8588
θ = 30.82°
Answer:
840 cm
Explanation:
Note: A hydraulic press operate based on pascal's principle.
From pascal's principle
W₁/d₁ = W₂/d₂...................... Equation 1
Where W₁ and W₂ are the first and second weight, and d₁ and d₂ are the first and second diameter of the piston.
make d₁ the subject of the equation
d₁ = W₁×d₂/W₂................ Equation 2
Given: W₁ = 2100 kg, W₂ = 25 kg, d₂ = 10 cm = 0.1 m.
Substitute these values into equation 2
d₁ = 2100(0.1)/25
d₁ = 8.4 m
d₁ = 840 cm