Answer:
D is not the a vector quantities
According to the US green building council, the US building account for 39% of world primary energy consumption . Electricity has approximately 78% of total building energy consumption and also contributes to GHG emissions
Answer:
40%
Explanation: United States Green Building Council is a body aimed at ensuring reduced green house gas emissions from activities taking place in building. they carry out surveys, carry out enlightenment activities and release the reports of and trending green house emission issues all these are to guarantee safe and healthy living for all. A total of 40% of Green house emissions are from buildings from the construction stage to it usage.
impact populations?
Answer:
it represents a fundamental difference. (more info below)
Explanation:
Production is incessantly developing and expanding in socialist countries, and employment is guaranteed for the entire productive population. Consequently, the relative overpopulation problem has been eliminated. This represents the fundamental difference between socialism's demographic law and capitalism's law.
hope this helped!
Distance traveled by the bicycle during the 5 seconds of braking is 22m
Explanation:
initial angular velocity= 2 rev/s
final angular velocity= 0 rev/s
Angular displacement Ф=t
Ф= rev
so the distance travelled= 5(2πr)
distance=5(2π*0.7)
distance=22m
The bicycle traveled about 22 m during the 5.0 seconds of braking
Centripetal Acceleration can be formulated as follows:
a = Centripetal Acceleration ( m/s² )
v = Tangential Speed of Particle ( m/s )
R = Radius of Circular Motion ( m )
Centripetal Force can be formulated as follows:
F = Centripetal Force ( m/s² )
m = mass of Particle ( kg )
v = Tangential Speed of Particle ( m/s )
R = Radius of Circular Motion ( m )
Let us now tackle the problem !
Given:
radius of wheel = R = 0.70 m
initial angular speed = ω = 2.0 rev/s = 4π rad/s
final angular speed = ωo = 0 rad/s
time taken = t = 5.0 s
Asked:
distance covered = d = ?
Solution:
Grade: High School
Subject: Physics
Chapter: Circular Motion
Answer:
2.70
Explanation:
pH = -log[H+]
pH = -log[2.0x10^-3]
pH = 2.70
b. The objects will collide and bounce back with a larger velocity.
c. The objects will collide and stay stationary.
d. The objects will collide and move forward in one direction.
0.46Ω
The electromotive force (E) in the circuit is related to the terminal voltage(V), of the circuit and the internal resistance (r) of the battery as follows;
E = V + Ir --------------------(a)
Where;
I = current flowing through the circuit
But;
V = I x Rₓ ---------------------(b)
Where;
Rₓ = effective or total resistance in the circuit.
First, let's calculate the effective resistance in the circuit:
The effective resistance (Rₓ) in the circuit is the one due to the resistances in the two lightbulbs.
Let;
R₁ = resistance in the first bulb
R₂ = resistance in the second bulb
Since the two bulbs are both rated at 4.0W ( at 12.0V), their resistance values (R₁ and R₂) are the same and will be given by the power formula;
P =
=> R = -------------------(ii)
Where;
P = Power of the bulb
V = voltage across the bulb
R = resistance of the bulb
To get R₁, equation (ii) can be written as;
R₁ = --------------------------------(iii)
Where;
V = 12.0V
P = 4.0W
Substitute these values into equation (iii) as follows;
R₁ =
R₁ =
R₁ = 36Ω
Following the same approach, to get R₂, equation (ii) can be written as;
R₂ = --------------------------------(iv)
Where;
V = 12.0V
P = 4.0W
Substitute these values into equation (iv) as follows;
R₂ =
R₂ =
R₂ = 36Ω
Now, since the bulbs are connected in parallel, the effective resistance (Rₓ) is given by;
= + -----------------(v)
Substitute the values of R₁ and R₂ into equation (v) as follows;
= +
=
Rₓ =
Rₓ = 18Ω
The effective resistance (Rₓ) is therefore, 18Ω
Now calculate the current I, flowing in the circuit:
Substitute the values of V = 11.7V and Rₓ = 18Ω into equation (b) as follows;
11.7 = I x 18
I =
I = 0.65A
Now calculate the battery's internal resistance:
Substitute the values of E = 12.0, V = 11.7V and I = 0.65A into equation (a) as follows;
12.0 = 11.7 + 0.65r
0.65r = 12.0 - 11.7
0.65r = 0.3
r =
r = 0.46Ω
Therefore, the internal resistance of the battery is 0.46Ω
Answer:
Explanation:
Internal resistance is a concept that helps model the electrical consequences of the complex chemical reactions that occur within a battery. When a charge is applied to a battery, the internal resistance can be calculated using the following equation:
Where:
As you can see, we don't know the exactly value of the . However we can calculated that value using the next simple operations:
The problem tell us that the power of each lightbulb is 4.0 W at 12.0 V, hence let's calculated the power at 11.7V using Cross-multiplication:
Solving for :
Now, the electric power is given by:
Where:
So:
Now, because of the lightbulbs are connected in parallel the equivalent resistance is given by:
Finally, now we have all the data, let's replace it into the internal resistance equation: