Answer:
6.67 ohm
Explanation:
From the question given above, the following data were obtained:
Resistor 1 (R₁) =20 ohm
Resistor 2 (R₂) = 20 ohm
Resistor 3 (R₃) = 20 ohm
Equivalent Resistance (R) =?
Since the resistors are arranged in parallel connection, the equivalent resistance can be obtained as follow:
1/R = 1/R₁ + 1/R₂ + 1/R₃
1/R = 1/20 + 1/20 + 1/20
1/R = (1 + 1 + 1) / 20
1/R = 3/20
Invert
R = 20/3
R = 6.67 ohm
Therefore, the equivalent resistance is 6.67 ohm.
Answer:
The mass of the wheel is 2159.045 kg
Explanation:
Given:
Radius 
m
Force
N
Angular acceleration 
From the formula of torque,
Γ
(1)
Γ
(2)

Find momentum of inertia
from above equation,



Find the momentum inertia of disk,



Kg
Therefore, the mass of the wheel is 2159.045 kg
Speed has only magnitude and no direction.
Option D) A drop of mercury is both a pure substance and and element.
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