(1) Assume that the lights in your kitchen use 300 watts. How much energy (in kWh) does it use and how much does it cost to leave the lights on 24 hours a day for one year if electricity is 12cents/kilowatt hour
Answer:
the cost to leave the lights on 24 hours a day for one year is 31,536 cents or 315.36 dollars
Explanation:
Given that;
P = 300 watts = 300/1000 = 0.3
t = 24hrs a day
In a calendar year, we have 365 days
so;
E = 0.3 × 365 × 24
E = 2628 KWh
given that; 1 KWh = 12 cent
then 2628 KWh is x
x = 2628 × 12
x = 31,536 cents or 315.36 dollars
Therefore, the cost to leave the lights on 24 hours a day for one year is 31,536 cents or 315.36 dollars
One limitation about science is that he cannot answer questions about
A. Ancient geography
B. Planets outside the solar system
C. Value
D. Black holes
Answer:
C. Value
Explanation:
Science is the study of natural and observable measurable phenomenon based on evidence.
Science is not able to answer questions related to value because they are not based on on evidence or facts. Questions related to value can not be answered through scientific investigation.
Hence, the correct answer is "C. Value".
a wye-connected load has a voltage of 480v applied to it. What is the voltage drop across each phase
Answer:
[tex]Y_A=277.128 \angle 30v[/tex]
[tex]Y_B=277.128 \angle (-150)v[/tex]
[tex]Y_C=277.128 \angle (90)v[/tex]
Explanation:
From the question we are told that
Voltage [tex]V_L_L =480v[/tex]
Generally in a case of Y_connection [tex]V_p_ h[/tex] is mathematical represented as
[tex]V_p_h=\frac{V_l_l}{\sqrt{3}} \angle (\phi-30)v[/tex]
Generally voltage drop across phase A
[tex]Y_A=\frac{408}{\sqrt{3}} \angle -(0-30)[/tex]
[tex]Y_A=277.128 \angle 30v[/tex]
Generally voltage drop across phase B
[tex]Y_B=277.128 \angle (-30-120)[/tex]
[tex]Y_B=277.128 \angle (-150)v[/tex]
Generally voltage drop across phase C
[tex]Y_C=277.128 \angle (-30+120)[/tex]
[tex]Y_C=277.128 \angle (90)v[/tex]
If the two particles that make up the dipole are 2.5 mm apart, what is the magnitude of the charge on each particle
This question is incomplete, the complete question is;
The electric force due to a uniform external electric field causes a torque of magnitude 20.0 × 10⁻⁹ N⋅m on an electric dipole oriented at 30° from the direction of the external field. The dipole moment of the dipole is 7.5 × 10⁻¹² C⋅m.
What is the magnitude of the external electric field?
If the two particles that make up the dipole are 2.5 mm apart, what is the magnitude of the charge on each particle?
Answer:
- the magnitude of the external electric field is 5333.3 N/C
- the magnitude of the charge on each particle is 3.0 × 10⁻¹² C ≈ 3 nC
Explanation:
Given that;
Torque = 20.0 × 10⁻⁹ N⋅m
dipole moment = 7.5 × 10⁻¹²
∅ = 30°
The moment T of restoring couple is;
T = PEsin∅
E = T/Psin∅
we substitute
E = 20.0 × 10⁻⁹ N⋅m / (7.5 × 10⁻¹²) sin(30°)
E = 20.0 × 10⁻⁹ / 3.75 × 10⁻¹²
E = 5333.3 N/C
Therefore, the magnitude of the external electric field is 5333.3 N/C
The dipole moment is given by the expression;
p = ql
q = p / l
given that l = 2.5 mm = 0.0025 m
we substitute
q = 7.5 × 10⁻¹² / 0.0025
q = 3.0 × 10⁻¹² C ≈ 3 nC
Therefore, the magnitude of the charge on each particle is 3.0 × 10⁻¹² C ≈ 3 nC
PLEASE HELP!! what is newton’s second law?
Newton's second law - the law of acceleration (acceleration = force/mass). Newton's second law states that the acceleration of an object is directly related to the net force and inversely related to its mass. Acceleration of an object depends on two things, force and mass.
Which two mixtures are homogeneous?
D A. Gasoline
B. Apple juice
C. Pie crust
D. Cereal in milk
Answer:
A. Gasoline
B. Apple juice
Explanation:
A homogeneous mixture can be defined as any liquid, solid or gaseous mixture which has an identical or uniform composition and properties throughout any given sample of the mixture. In Chemistry, all solutions are considered to be a homogeneous mixture.
For instance, aqueous hydrogen chloride, HCl(aq) is a homogeneous mixture. The aqueous hydrogen chloride is a homogeneous mixture of water and hydrogen chloride. This ultimately implies that, aqueous hydrogen chloride HCl(aq) is a solution of hydrogen chloride in water and it is commonly referred to as Hydrochloric acid.
Hence, the two mixtures that are homogeneous are gasoline and apple juice.
Answer:
A. Gasoline
B. Apple juice
A homogeneous mixture is a mixture in which the composition is uniform throughout the mixture. The salt water described above is homogeneous because the dissolved salt is evenly distributed throughout the entire salt water sample. Often it is easy to confuse a homogeneous mixture with a pure substance because they are both uniform. The difference is that the composition of the substance is always the same. The amount of salt in the salt water can vary from one sample to another. All solutions would be considered homogeneous because the dissolved material is present in the same amount throughout the solution.
One characteristic of mixtures is that they can be separated into their components. Since each part of the mixture has not reacted with another part of the mixture, the identities of the different materials is unchanged.
Hence, the two mixtures that are homogeneous are gasoline and apple juice
Explanation:
NEED HELP ASAP!!!!!
A car speeds up from 15 m/s to 30 m/s in 12 seconds. What is the acceleration of the car?
A. 1.25 m/s2
B. 0.8 m/s2
C. 1.50 m/s2
D. 1.75 m/s2
Answer:
A, 1.25m/s^2
Explanation:
use formula v=v0+at to solve for a
a= v-v0/t
Plug in givens
30-15/12 to get 15/12 = 1.25m/s^2
A woman, driving a golf ball off of the tree, gives the ball a speed of 20.0m/s. The mass of the ball is 45g and the duration of the impact with the golf club is 6.0x10^3
a) What is the change in the momentum of the ball?
b) Determine the average force applied by the club.
Answer:
See the answers below.
Explanation:
a)
The change in momentum can be calculated by means of the following equation.
[tex]P=m*v[/tex]
where:
P = momentum [kg*m/s]
m = mass = 45 [g] = 0.045 [kg]
v = velocity = 20 [m/s]
[tex]P=20*0.045\\P=0.9[kg*m/s][/tex]
b)
The change in momentum can also be calculated by means of the product of force by the duration time of the impact.
[tex]F*t=P\\F*0.006=0.9\\F=0.9/0.006\\F =150 [N][/tex]
If an object exerts a pressure of 12lb/in2 and it has an area of 0.2 in2 squared what is the weight of the object? Hint: weight is a force.
Answer:
Explanation:
As we know that ,
P=F/A
Where P=12 lb/in² and A= 0.2 in²
Putt in formula to get F ( weight of body)
F=12*0.2
F=2.4 Ib
Fern life begins as _____.
a spore
a sperm
an egg
HELP ASAP!
on the screenshot.
PLEASE HELP!! URGENT!!
Answer:
1. Gravity
2. Increases
Explanation:
Gravity is the force that attracts all objects toward each other. This is the force that keeps us grounded on Earth instead of floating in the air.
Although people have gravitational forces, the attraction force is a negligible amount. However, as the mass of the objects are increased, they will exert far greater gravitational powers to other objects or individuals such as humans.
Daisy walks across a force platform and the forces exerted by her foot during a step are recorded. The peak vertical reaction force is 1200 N (this force acts upward on Daisy). At the same instant, the braking frictional force is 200 N (this force acts backward on Daisy). How large is the resultant of these two forces? What is the direction of the resultant force?
Answer:
The direction of the resultant force is approximately 189.462º.
The magnitude of the resultant force is approximately 1216.553 newtons.
Explanation:
Let consider postive the direction of motion of Daisy's foot and the upward direction (perpendicular to direction of motion). Friction ([tex]f[/tex]), measured in newtons, is directed against motion, whereas normal force from ground to the foot ([tex]N[/tex]), measured in newtons, is in the upward direction. Then, resulting direction must be greater than 180º but less than 270º with respect to the axis of the direction of motion, which is found by the following formula:
[tex]\theta = 270^{\circ}-\tan^{-1} \frac{N}{f}[/tex] (1)
Where [tex]\theta[/tex] is the direction of the resultant force, measured in sexagesimal degrees.
If we know that [tex]N = 1200\,N[/tex] and [tex]f = 200\,N[/tex], then the direction of the resultant force is:
[tex]\theta = 270^{\circ}-\tan^{-1} \frac{1200\,N}{200\,N}[/tex]
[tex]\theta \approx 189.462^{\circ}[/tex]
The direction of the resultant force is approximately 189.462º.
The magnitude of the resultant force ([tex]F[/tex]), measured in newtons, is determined by Pythagorean Theorem:
[tex]F = \sqrt{f^{2}+N^{2}}[/tex]
[tex]F =\sqrt{(200\,N)^{2}+(1200\,N)^{2}}[/tex]
[tex]F \approx 1216.553\,N[/tex]
The magnitude of the resultant force is approximately 1216.553 newtons.
What allows a star to remain in stellar equilibrium?
Explanation:
A star is in equilibrium when the pressures inside the star balance out the force of gravity. The pressure is thermal pressure resulting from the fusion reactions taking place in the star's core. A star stays in equilibrium until the supply of hydrogen in the core is depleted.
In a stable star, the gas pressure pushing out from the center is equal with the gravity pulling atoms inward to the center – when these forces are equal, the star is at equilibrium. Once a star reaches equilibrium for the first time, it will start burning (fusing) hydrogen into helium.
Answer: It has enough mass to resist expansion.
15 POINTS PLZ HELP IM ON A TIMER! IM ON EDGE EXAM
Which describes pressure during a volcanic eruption?
Pressure increases as magma rises.
Pressure traps dissolved gases in magma.
Pressure increases until the volcano explodes.
Pressure from rocks above causes new rocks to form.
Answer:
B.) Pressure traps dissolved gases in magma
Explanation:
I hope this answer is correct
Answer:
B
Explanation:
explain the process of
anomalous expansion of water
The anomalous expansion of water refers to the fact that water, unlike most substances, expands when it freezes. The density of water increases as temperature decreases but reaches a maximum at 4° C then begins to expand.
When liquid water is cooled, it contracts like one would expect until a temperature of approximately 4 degrees Celsius is reached. After that, it expands slightly until it reaches the freezing point, and then when it freezes it expands by approximately 9%.
Now that you have one of the two variables in Part D, use substitution to solve for the two variables. You may want to review the
Answer: in cases neither of two equations in the system will contain a variable.
Explanation:
What three statements are true about the wave shown?
Consider a neutron star with a mass equal to the sun, a radius of 10 kmkm, and a rotation period of 1.0 ss. What is the speed of a point on the equator of the star
Answer:
6.28 * 10⁴ m/s
Explanation:
Using the relation :
Given :
Radius, R = 10km
Period, T = 1.0 s
v = (2πR) / T
Where v = velocity of a point
R in meters ;
1km = 1000m = 10³m
10km = 10 * 10³m = 1 * 10^4 m
v = (2π*10^4m) / 1 s
v = 6.2831853 * 10⁴ m/s
v = 6.28 * 10⁴ m/s
During her last physical exam before takeoff, an astronaut was told that her weight was within the acceptable range required for astronauts. After she was in space for two weeks, her weight was recorded again. Which is the best explanation for the astronaut's significant weight loss? A. As mass increases, weight decreases. B. There is less gravitational force affecting her in space. C. She lost body mass during the flight due to a decrease in metabolism. D. The amount of matter in a body decreases as the distance from Earth increases.
Answer:
The most likely answer is option C: She lost body mass during the flight due to a decrease in metabolism.
Explanation:
There are different theories regarding this. One of fact is that astronauts drink and eat considerably less than normal during the first day of flight (probably due to sickness before adaptation). It is thought that their bodies adapt to the changes in accelerations they suffer during the trip and in space.
A drone is flying horizontally when it runs out of power and begins to free fall from 16 m. No drag. If it lands 40 m away (in the x-direction) from where it began to fall, what was its horizontal velocity while it was falling
Answer:
the horizontal velocity while it was falling is 22.1 m/s.
Explanation:
Given;
height of fall, h = 16 m
horizontal distance, x = 40 m
The time to travel 16 m is calculated as;
[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2\times 16}{9.8} } \\\\t = 1.81 \ s[/tex]
The horizontal velocity is calculated as;
[tex]v_x = \frac{X}{t} \\\\v_x = \frac{40}{1.81} \\\\v_x = 22.1 \ m/s[/tex]
Therefore, the horizontal velocity while it was falling is 22.1 m/s.
The horizontal velocity while it was falling is
[tex]22.1m/s[/tex]What is horizontal velocity?Horizontal velocity becomes important for objects moving in a horizontal direction. Generally, horizontal velocity is horizontal displacement divided by time, such as mph or m/s.
Therefore, from equation of motion
[tex]Time, t = \sqrt\frac{2h}{g}\\\\t = \sqrt\frac{2*16}{9.8}\\\\t = 1.81sec[/tex]
Therefore, the horizontal velocity, [tex]V_h[/tex]
[tex]V_h = \frac{x}{t}\\\\V_h = \frac{40}{1.81}\\\\V_h = 22.09 or 22.1m/s[/tex]
For more information on horizontal velocity, visit
https://brainly.com/question/24681896
A gorilla drags a log across the jungle floor. The log begins at rest and accelerates at until the gorilla is moving at a fast lope. The coefficient of kinetic friction between the log and the mud and plants of the jungle is . Assume that friction and the gorillas pulling force remain constant the whole time. What frictional force acts on the log
Answer:
fr = 245 N, T = fr
Explanation:
We can solve this exercise using the equilibrium conditions, let's start by creating a reference system
where we call T the drag force of the gorilla, m the mass of the trunk and μ the coefficient of kinetic friction
Y axis
N- W =
N = W = mg
X axis
T - fr = 0
T = fr
the expression for the friction force is
fr = μ N
fr = μ mg
we substitute
T = μ m g
When analyzing these expressions we see that when the trunk reaches the maximum speed that the gorilla carries, the friction force is equal to the gorilla's tension
fr = T
for a specific calculation we must assign values to:
μ = 0.25
m = 100 kg
let's calculate
T = 0.25 100 9.8
T = 245 N
therefore for this case
fr = 245 N
Which evidence best supports that a device is an electric motor?
A. Electricity flows when a coil of wire is rotated by a hand crank.
B. Electricity flows from a battery through a loop of wire which then causes a needle to move.
C. Electricity flows from a battery to loop of wire and then through a galvanometer back to the battery.
D. Electricity flows through a coil of wire that is rotating because a magnet is pushing on the coil of wire.
Answer:
C
Explanation:
Answer:
the answer to this question is D
Explanation:
hope its helps
have a great day
Describe the way the light travels when you see a car behind you in the rear view mirror
Answer:
Described below
Explanation:
When you see a car behind you in the rear view mirror, it means that light rays travelling from the right hand side of the car driver behind are being reflected by the mirror to get to your eyes on the right side of the light rays from the drivers left hand side.
A soccer player is running to the right at 3.2m/s when a 0.50kg ball travelling at 5.0 m/s to the left collides their 5.0kg head. If the player's head velocity after the collision is 2.5 m/s to the right, what is the new velocity of the ball?
Answer:
300 m/s
Explanation:
Step one:
Given data
Mass of players head m1= 5kg
The initial velocity of players head u1= 3.2m/s
mass of ball m2= 0.5kg
Initial velocity of ball= 5 m/s
Final velocity of player= 2.5 m/s
Required
The velocity of the ball after collision
Step two:
Applying the conservation of momentum formula for elastic collision
m1u1+m2u2= m1v1+m2v2
substitute
5*32+0.5*5= 5*2.5+0.5*v2
160+2.5= 12.5+0.5v2
collect like terms
162.5-12.5= 0.5v2
150= 0.5v2
divide both sides by 0.5
v2= 150/0.5
v2=300 m/s
The new velocity of the ball is 300 m/s
sum it up a cornell doodle notes
A car, travelling at constant speed on a straight, level road, accelerates so that its speed is now doubled. By what factor will the car's kinetic energy change? Explain by using physics
principles
Answer:
We know that, the kinetic energy
ke= \frac{1 }{2} m{v}^{2}
and we also know that the acceleration causes the speed's value to be doubled
Hence, v becomes 2v
When 2v is squared, it becomes 4v^2. After substituting this value in the equation above and comparing it,
We can conclude that the Kinetic Energy has increased
by a factor of 4
The sun uses what energy to gases, which causes particles to speed up, spread out, and rise up mark as brainlest. ASP Pls
Answer:
Heat causes the molecules to move faster, (heat energy is converted to kinetic energy ) which means that the volume of a gas increases more than the volume of a solid or liquid.
Through nuclear fusion, the sun is constantly using up the hydrogen in its core: Every second, the sun fuses around 620 million metric tons of hydrogen into helium. At this stage in the sun's life, its core is about 74% hydrogen.
4. A driver takes 3.5 s to react to a complex situation. How far does the vehicle travel before the driver initiates a physical response to the situation (i.e., putting his or her foot on the brake)
This question is incomplete, the complete question is;
A driver takes 3.5 s to react to a complex situation while driving at a speed of 60 mi/h.
How far does the vehicle travel before the driver initiates a physical response to the situation (i.e., putting his or her foot on the brake)
Answer:
the distance travelled by the vehicle, before the driver initiates a physical response is 308 ft
Explanation:
Given that;
Reaction time t = 3.5 sec
Speed S = 60 mi/h
we convert mile to foot and hour to seconds
so
Speed S = 60 mi/h = (60×5280)/(60×60) = 316800/3600 = 88 ft/sec
Now, The distance travelled by vehicle before the driver initiates physical response is equal to Lag distance. i.e
Lag distance = V × t
we substitute
Lag distance = 88 ft/sec 3.5 sec
Lag distance = 308 ft
Therefore, the distance travelled by the vehicle, before the driver initiates a physical response is 308 ft
the study of physical world is called?
Answer:
Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, Earth science, and astronomy.
