Answer:
<em>The thermal energy dissipated in A would be twice that in B</em>
Explanation:
Resistor B (RB)= R
Resistor A (RA)= 2 R
When they are connected in series the equivalent Resistance in the circuit would be;
Equivalent resistance = RA +RB = R + 2 R = 3 R;
From ohms law I = V/R
I = V/3 R
Now the thermal energy is the power dissipated by the circuit and can be obtained thus;
P =
Then,

Therefore Pa : Pb = 2: 1, this means that the thermal energy dissipated in A would be twice that in B
The answer is commensalism because commensalism is a relationship where an organism is benefitted and the other is neither benefitted nor harmed. The barnacle is being benefited and the whale is not being benefited or harmed.
Short Answer
3: C
4: D
Problem Three
Remark
Somewhere we ought to be told that this is the Doppler Effect. I have never done a problem using this formula, so I think I'm doing it correctly, but no guarantees. My guess is that the frequency increases as it comes towards you and decreases as it moves away from you. I think that is correct.
Formula
<em><u>Givens</u></em>
- f' = observed frequency
- f = actual frequency
- v = velocity of sound or light waves.
- vo = velocity of observer (in both cases 0)
- vs = velocity of source.
f' = (v + vo) * f / (v - vs)
Solution
- v = 3*10^8 m/s
- f' = 1.1 f
- f = f
- vo = 0 We are standing still while all this is going on.
- vs = ???
f'/f = 1.1
1.1 = (3*10^8 + 0 ) / (3*10^8 - vs)
3.3*10^8 - 1.1*vs = 3*10^8
3.3*10^8 - 3*10^8= 1.1 vs
0.3 * 10^8 = 1.1 vs
2.73 * 10^7 = vs
The closest answer is 3.00 * 10^7 which is C
Problem Four
Here what is happening is that you are looking for the frequency resulting from a wave moving towards you at 1/2 the speed of sound. You are not moving.
<em><u>Givens</u></em>
- v = v
- vs = 1/2 v
- f ' = ?
- f = 1000 hz
- vo =0
f' = v/(v - 1/2v) * 1000
f' = v/ (1/2 v) * 1000
f' = 2 * 1000
f' = 2000 which is D
Answer:
The angle is 18.3 degree.
Explanation:
A uniformly charged infinite plane, density σ = 4 x 10^-9 C/cm^2, is placed vertically in air. A small ball of mass 8 g, with charge q = 10^-8 C, hangs close to the plane, so that the string is initially parallel to the plane. Take g = 9.8m/s2. When in equilibrium, by what angle is the string hanging the ball to the plane?
surface charge density, σ = 4 x 10^-5 C/m^2
Charge, q = 10^-8 C
mass, m = 0.008 kg
Let the angle is A and the tension in the string is T.
The electric field due to a plane is

Now equate the forces,
