Explanation:
The kilogram (kg) is defined by taking the fixed numerical value of the Planck constant h to be 6.62607015 ×10−34 when expressed in the unit J s, which is equal to kg m2 s−1, where the meter and the second are defined in terms of c and ∆νCs.
A water heater marked 4 kW takes 4 minutes to heat 1 kg of water from 20 °C to 50 °C. The cost of electrical energy per kWh
is $0.120. What will be the total cost of energy consumption?
The total cost of the energy consumption for the given time period is $0.0364
The given parameters include;
power rating of the heater, P = 4 kW = 4000 Wtime taken to completely boil the water,[tex]t = 4 \min = 4 \min \times \frac{1 \ h}{60 \ \min} = 0.067 \ h[/tex]mass of the water, m = 1 kginitial temperature of the water, t₁ = 20 ⁰Cfinal temperature of the water, t₂ = 50 ⁰Cspecific heat capacity of water, c = 4200 J/kg⁰Ccost of electrical energy = $0.12The total energy consumed in the process of heating the water;
Total electrical Energy = Energy of the heater (kWh) + Energy of the heated water (kWh)
Energy of the heater (kWh) = power x time
= 4 kW x 0.067 h
= 0.268 kWh
Energy of the heated water (J) = mcΔt
where;
Δt is the change in temperature = t₂ - t₁
= 50 ⁰C - 20 ⁰C = 30⁰C
Energy of the heated water (J) = 1 x 4200 x 30
= 126,000 J
Electrical power of the heated water (Watts) = [tex]\frac{126,000 \ J}{4 \ \min} \times \frac{1 \min}{60 \ s} = 525 \ W[/tex]
Energy of the heated water (kWh) = [tex]\frac{525}{1000} \times 4\min\times \frac{1 \ hr}{60 \min} = 0.035 \ kWh[/tex]
Total electrical Energy = 0.268 kWh + 0.035 kWh
= 0.303 kWh
The total cost of the energy consumed is calculated as;
[tex]Total \ cost = \frac{\$ \ 0.12}{kWh} \times 0.303 \ kWh = \$ \ 0.0364[/tex]
Therefore, the total cost of the energy consumption is $0.0364
To learn more about cost of electrical energy calculation, please visit: https://brainly.com/question/17924004
Question 3 of 10
Which image shows an example of the strong nuclear force in
action?
A.
B.
C.
D.
Answer: The answer is B
Explanation:
There are 4 fundamental forces that hold matter together.
- Gravitational Force
- Electromagnetic Force
- Strong Nuclear Force
- Weak Nuclear Force
We have barely just scratched the info about nuclear forces but the reason why B is the answer to the question is that Strong nuclear force actually holds the protons and neutrons together in the nucleus of an atom, much like the picture in B.
Answer: B
Explanation:
The pressure at the ice point for a constant-volume gas thermometer is 4.81 x 10^4Pa.
While that at the steam point is 6.48 x 10^4 Pa.
What pressure would the thermometer indicate at 50°c?
Answer:
0 deg C = 4.81E4 pressure at 0 deg
100 deg C = 6.48E4 pressure at steam point
100 deg C - 50 deg C = (6.48 - 4.81) * 10^4 = 1.67E4 Pa
50 deg C = 50 / 100 * 1.67E4 + 4.81E4 = 5.65E4 Pa Just the halfway point between the two given pressures
What is the total distance covered during its complete motion? (CCT TYPE) *
2 points
350 km
20/3 km
50 km
40/3 km
What is the SI unit of speed? ( CCT type) *
2 points
m/s
mm/s
m/ss
None of the above
. In which period is the bus decelerating? (CCT type) *
2 points
0-5 min
8- 12 min
11-19 min
5-10 min
Only answer who knows, don't spam. because I am in hurry.
Answer:
40/3
M/s
11-19
These are the answers
A bucket filled woth water seems light while it sinks into water.Also show their relation using formula
Answer: This phenomenon happens due to upthrust exerted by water.
Explanation:
We know that,
Liquid Pressure is directly proportional to the height of the vertical column in the liquid.(P∝h)
When a bucket filled water is sunk into the water container, there occur difference in the pressure in top and bottom of the water container. Due to this, water exerts an upward force on the bucket filled with water. This is called Uprthrust.
Upthrust on the bucket makes the bucket filled with water lose some of it's weight and causes apparent loss in weight.
Hence, the bucket filled with water seems light while it sinks into water.
State Ohms law in easy words
Answer:
Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points.
A ball is dropped from a height of 180m- Calculate the velocity of the ball when it strikes the ground
Answer:
6s , 60mls
Explanation:
hope this helps love
Answer:
0m/s
Explanation:
When the object strikes the ground, it then becomes in uniform motion and when an object is in uniform motion, the velocity is 0
which statement accurately describes how the acceleration of an object in free fall changes
Answer:
A ball rolls off the table and free falls to the ground. Which statement accurately describes its acceleration? Its acceleration is downward but remains a constant value as it falls.
Starting from rest, two skaters push off against each other on smooth level ice, where friction is negligible. One is a woman and one is a man. The woman moves away with a velocity of 1.9 m/s relative to the ice. The mass of the woman is 46 kg, and the mass of the man is 88 kg. Assuming that the speed of light is 3.0 m/s, so that the relativistic momentum must be used, find the recoil velocity of the man relative to the ice.
304 divided by 2.52
8001 divided by 3.5
820 divided by 6.9
Answer:
dude just use the calculator fr
please mark this answer as brainlist
Enample: the motion of moon around the earth Describe the motion of an object in which its speed constant but the velocity is changing
Answer:
To summarize, an object moving in uniform circular motion is moving around the perimeter of the circle with a constant speed. While the speed of the object is constant, its velocity is changing. Velocity, being a vector, has a constant magnitude but a changing direction.
Explanation:
Speed refers to how fast an object is moving. It can be thought of as the rate at which an object covers distance.
Velocity refers to the rate at which an object changes its position. If you picture a person moving rapidly - one step forward and one step back- always returning to the original starting position, the speed is very rapid, but the velocity is zero. Because the person always returns to the original position, this motion would bébé result in a change in position. Since velocity is defined as the rate at which the position changes, this motion results in zero velocity. To maximize velocity, every effort must be made to maximize the amount an object is displaced from its original position. Every movement should be moving the object further from where it started. Velocity is DIRECTION AWARE. When evaluating the velocity of an object, you have to keep track of direction. This is one of the essential differences between speed and velocity: speed does not keep track of direction, while velocity is directionally aware.
So, when the moon moves around the Earth, the speed remains constant, but since it's moving in an elliptical orbit, it's direction is constantly changing.
show how three identical 6 resistors must be connected tho have the following effective resistance values 9 and 4 ohms
Answer:
connect two 9 ohms resistance in series now it becomes 18 ohm
People who get population education are also aware of health issues and environment education justify
Observe the given figure and find the the gravitational force between m1 and m2.
Answer:
The gravitational force between m₁ and m₂, is approximately 1.06789 × 10⁻⁶ N
Explanation:
The details of the given masses having gravitational attractive force between them are;
m₁ = 20 kg, r₁ = 10 cm = 0.1 m, m₂ = 50 kg, and r₂ = 15 cm = 0.15 m
The gravitational force between m₁ and m₂ is given by Newton's Law of gravitation as follows;
[tex]F =G \cdot \dfrac{m_{1} \cdot m_{2}}{r^{2}}[/tex]
Where;
F = The gravitational force between m₁ and m₂
G = The universal gravitational constant = 6.67430 × 10⁻¹¹ N·m²/kg²
r₂ = 0.1 m + 0.15 m = 0.25 m
Therefore, we have;
[tex]F = 6.67430 \times 10^{-11} \ N \cdot m^2/kg \times \dfrac{20 \ kg\times 50 \ kg}{(0.1 \ m+ 0.15 \ m)^{2}} \approx 1.06789 \times 10^{-6} \ N[/tex]
The gravitational force between m₁ and m₂, F ≈ 1.06789 × 10⁻⁶ N
Why do scientists not use US customary units when reporting their data?
One of the scientist's jobs is to report the results of his experiments to all the other scientists in the world.
There isn't a single real science shop anywhere in the world that uses the US customary system of units. Not one.
Even in the measly three countries that use it for measuring carpet, pumping gas, and weighing fish ... Myanmar, Liberia, an the USA ... the scientists do their work in the SI/MKS/metric system.
Write the dimension of a / b in the x = at + bt2. Where x is the distance and t is the time?
The dimension of a/b where x is the distance and t is the time is T
Given the expression
x = at + bt²
where
x is the distance
t is the time
Based on the homogeneity principle, the expression on the left-hand side must be equal to that on the right. Hence;
x = at
[tex]a = \frac{x}{t}[/tex]
Since x is the distance and distance is measured in metres, the dimension equivalent will be the length 'L'
Since t is the time and time is measured in seconds, the dimension equivalent will be the seconds 'T'
[tex]a=\frac{L}{T}[/tex]
Similarly;
x = bt²
[tex]b=\frac{x}{t^2}\\b=\frac{L}{T^2}[/tex]
Next is to get a/b;
[tex]\frac{a}{b} = \frac{L}{T} \div \frac{L}{T^2}\\\frac{a}{b} = \frac{L}{T}*\frac{T^2}{L} \\\frac{a}{b} =\frac{T^2}{T}\\\frac{a}{b} =T[/tex]
Hence the dimension of a/b is T
What volume of silver metal will have a mass of exactly 2500.0 g? The density of silver is 10.50 g/cm3.
*Include your units!
Round your answer to the nearest tenth.
Explanation:
The density of silver is 10.5g/cm3
=2500.0g/10.5g/cm3
=238.09cm3
238.1cm3 to nearest tenth.
I hope my answer helps. Please mark as brainliest.
What is the voltage of the power source if a motor with a resistance of 20 2 draws a
current of 1.5 A?
Answer:
190v I believe
hope this helped a little and if it did pls mark brainiest :)
The mass of an object is 4kg and it has a density of 5gcm^-3. what is the volume
Answer:
density = mass/ volume
5=4000/ volume
volume=4000/5
volume=800 cm^-3
6.
For a given prism the angle of incidence is changed from 0° and 90', the angle of deviation [ ]
b) decreases
c) first decreases and then increases
d) first increases and then decreases
a) increases
Answer:
increase
Explanation:
please mark as brainlyest
Answer
A.Increses
Explanation:
a stone attached to 1m long string is moving with the speed of 5ms in a circle find the centripetal acceleration of the stone
Answer:
The centripetal acceleration of the stone is 5 m/s²
Explanation:
The length of the string to which the stone is attached, r = 1 m
The speed with which the string is rotated, v = 5 m/s
The centripetal acceleration, [tex]a_c[/tex], is given as follows;
[tex]a_c = \dfrac{v^2}{r}[/tex]
Therefore, the centripetal acceleration of the stone found as follows;
[tex]a_c = \dfrac{(5 \ m/s)^2}{1 \ m} = 5 \ m/s^2[/tex]
The centripetal acceleration of the stone, [tex]a_c[/tex] = 5 m/s².
The radius of the base of a wooden cylinder 2m and its altitude is 7m. What is its mass?
Answer:
88 m ^2
Explanation:
solve two questions under inclined plane using Newton 2nd law
Explanation:
If the mass of the inclined plane is large enough, could N ever be equal to mgcosθ. Reasons?
So far I've come up with: mgcosθ−N=ma meaning if N were to equal mgcosθ, ma=0. Since the surfaces are frictionless and since N is acting on the inclined plane too(it'll have a horizontal component), this isn't possible. Am I right? Where am I going wrong?
Which type of reactions usually happens slowest?
Answer:
option b is correct..................
How do we find the weight of a beam
Answer:
Standard weight: We calculate the standard weight as follows: G = L * mweight, where L is the length of the beam calculated as the difference between the extreme points of the beam body along the direction of the beam axis, taking into account all features except holes.
Explanation:
I want Brainliest plz!!
: Lili
light travels 3,00,000 km/s . Is it velocity or speed?
Answer:
speed
Explanation:
according to your question, your answer is speed
give reason
Husking rice in a rice mill is faster than husking with dhiki
Answer:
Because rice mill is more advanced than dhiki.
It is the developed form of the dhiki.
If the resistance reading on a dmm’s meter face is 22.5 ohms and the range selector switch is set to the R x 100 range what’s the actual measured resistance of the circuit
A.22.5 kohms
B.2.25 mohms
C.2.25 kohms
D.225 ohms
Answer:
c
Explanation:
(6). A car travels in a straight line from city A to city B at a speed of 60kmh-1
. Then return
from city B to city A along the original route at a speed of 40kmh-1
. The distance between
the two cities is 120 km. What is the average speed of the vehicle?
1. 30kmh-1
2. 45kmh-1
3. 48kmh-1
4. 60kmh-1
Please help have due very soon?thank you
