Two 20 ohm resistors are connected in parallel and two 10 ohm resistors are connected in parallel. If these two combinations are
connected in series the equivalent resistance of the combination is: a) 20 ohm b) 10 ohm c) 15 Ohm d) 30 Ohm
1 answer:
C. 15Ω.
The circuit diagram is shown in the first image attached. To solve this problem we have to use the equivalent resistor conected in parallel Req = (R1*R2)/(R1+R2).
Calculating the equivalent resistor in the 20Ω resistor parallel arrangement:
RAeq = [(20*20)/(20+20)] Ω
RAeq = 400/40 Ω
RAeq = 10Ω
Calculating the equivalent resistor in the 10Ω resistor parallel arrangement:
RBeq = [(10*10)/(10+10)]Ω
RBeq = 100/20 Ω
RBeq = 5Ω
Both equivalent resistors are in series. So, in order to calculate the equivalent resistance of the combination:
Rtotal = RAeq + RBeq
Rtotal = 10Ω + 5Ω
Rtotal = 15Ω
You might be interested in
Answer:
T1 = 490.5 [N], T2 = 490.5[N]
Explanation:
First, we must draw a free body diagram of the steel ball hanging and the two wires holding it as well as the angle forming the wires between them.
The free-body diagram can be seen in the attached image.
As the cables are symmetrical with respect to the vertical axis, the force in cables 1 and 2 is equal, so when performing a force sum equal to zero on the Y-axis, we can find the force value of any cable.
The solution of the equations can be seen in the attached image
The increase in gravitational potential energy for an object of mass m is given by
where
is the increase in altitude of the object.
In our problem, m=3.0 kg,
and 
(approximated value), so we have
where
In our problem, m=3.0 kg,