Evaporation would be the answer.
First question (upper left):
1/Req = 1/12 + 1/24 = 1/8
Req = 8 ohms
Voltage is equal through different resistors, and V1 = V2 = 24 V.
Current varies through parallel resistors: I1 = V1/R1 = 24/12 = 2 A. I2 = 24/24 = 1 A.
Second question (middle left):
V1 = V2 = 6 V (parallel circuits)
I1 = 2 A, I2 = 1 A, IT = 2+1 = 3 A.
R1 = V1/I1 = 6/2 = 3 ohms, R2 = 6/1 = 6 ohms, 1/Req = 1/2 + 1/1, Req = 2/3 ohms
Third question (bottom left):
V1 = V2 = 12 V
IT = 3 A, meaning Req = V/It = 12 V/3 A = 4 ohms
1/Req = 1/R1 + 1/R2, 1/4 = 1/12 + 1/R2, R2 = 6 ohms
I1 = V/R1 = 1 A, I2 = V/R2 = 2 A
Fourth question (top right):
1/Req = 1/20 + 1/20, Req = 10 ohms
IT = 4 A, so VT = IT(Req) = 4*10 = 40 V
Parallel circuits, so V1 = V2 = VT = 40 V
Since the resistors are identical, the current is split evenly between both: I1 = I2 = IT/2 = 2 A.
Fifth question (middle right):
1/Req = 1/5 + 1/20 + 1/4, Req = 2 ohms
IT = VT/Req = 40 V/2 ohms = 20 A
V1 = V2 = V3 = 40 V
The current of 20 A will be divided proportionally according to the resistances of 5, 20, and 4, the factors will be 5/(5+20+4), 20/(5+20+4), and 4/(5+20+4), which are 5/29, 20/29, and 4/29.
I1 = 20(5/29) = 100/29 A
I2 = 20(20/29) = 400/29 A
I3 = 20(4/29) = 80/29 A
Sixth question (bottom right):
V2 = 30V is given, but since these are parallel circuits, V1 = VT = 30 V.
Then I1 = V1/R1 = 30 V/10 ohms = 3 A.
I2 = 30 V/15 ohms = 2 A.
IT = 3 + 2 = 5 A
1/Req = 1/10 + 1/15, Req = 6 ohms
Answer:
A) The possible algebraic signs will either be both positive (+) or both negative (-) charged since the 2 objects are repelling each other to stretch the string.
B) Magnitude of charges = 1.206 × 10^(-6) C
Explanation:
We are given;
Spring constant;k = 350 N/m
Spring length;L = 0.39 m
Stretched length of spring;x = 0.022 m
A) The spring stretches by 0.022m. Therefore, the total force is (350 × 0.022) N = 7.7N. The charged objects will either be both positive (+) or both negative (-) charged since they are repelling each other to stretch the string.
B) Force (F) required to stretch spring is given by the formula;
F = kx
Thus:
F = (350 × 0.022)
F = 7.7 N
Now, if we assume point charges, then the distance (r) between them will be given as:
r = (0.39 + 0.022) = 0.412 m
Coulomb's Law has a formula:
F = k(q1×q2)/r²
where k is coulomb's constant = 8.99 × 10^(9) Nm²/C²
Making q1 × q2 the subject, we have;
(q1 × q2) = Fr²/k = 7.7 × 0.412²/(8.99 × 10^(9))
(q1 × q2) = 14.54 × 10^(-11) C
We are told that both charges are equal, thus; |q1| = |q2|
So;
q = √(14.54 × 10^(-11)) = 1.206 × 10^(-6) C
Explanation:
for v vs t graph for t=9 to 11,v=15kmph
similarly v2=0,v3=60kmph&v4= -40kmph
