Answer:
[tex]\theta_2 = 34.61^0[/tex]
Explanation:
Path difference for the destructive interference of a single slit:
[tex]D sin \theta = n \lambda[/tex]
For the first - order minimum, n = 1, and [tex]\theta = \theta_1[/tex]
[tex]D sin \theta_1 = \lambda[/tex].........(1)
For the second - order minimum, n = 2, and [tex]\theta = \theta_2[/tex]
[tex]D sin \theta_2 = 2 \lambda[/tex].........(2)
Dividing equation (2) by equation (1):
[tex]\frac{D sin \theta_2}{Dsin \theta_1} = \frac{2 \lambda}{\lambda} \\\frac{ sin \theta_2}{sin \theta_1} = 2 \\\theta_1 = 16.5^0\\\frac{ sin \theta_2}{sin 16.5} = 2\\sin \theta_2 = 2 sin 16.5\\sin \theta_2 = 0.568\\\theta_2 = sin^{-1} 0.568\\\theta_2 = 34.61^0[/tex]
HELLLP PLEASE || the graph below shows a conversion of energy for a skydive jumping out of a plane and landing safely on the ground. which energy is represented by line A? A) Potential B) Thermal C) Kinetic D) Total Energy
Answer: If i'm not mistaken I think it A) potential
An electric dipole of dipole moment 'p' is placed in the position of stable equilibrium in a uniform field of intensity 'E'. The torque required to rotate, when the dipole makes an angle Ө with the initial position is pE cos Ө pE sin Ө p cos Ө p tan Ө
Answer:
Torque by electric dipole = pEcos thita
A wave has a frequency of 450 Hz and a wavelength of 0.52 m. What is the speed of the wave?
Answer:
Explanation:
ave speed is always (frequency) x (wavelength)
Speed = (450 /sec) x (0.52 m)
= 234 m/sec .
Most of the elements in the periodic table are___
Answer:
The most of the elements in the periodic table are metals. The elements cannot be gases and liquids (Molecules are mainly gases and liquids). Metalloids are few. Examples (Germanium, Arsenic)
Question 13 of 32
1 Point
For a satellite to orbit Earth at a constant distance, its centrifugal acceleration
must be equal and opposite Earth's gravitational acceleration. If a satellite is
to orbit at a constant distance from Earth at a circular radius of 7,000,000 m,
what is the required velocity of the satellite? (Assume the acceleration due to
Earth's gravity is 8.2 m/s2 at this altitude.)
O A. 8239 m/s
O B. 7576 m/s
C. 6818 m/s
D. 7043 m/s
Answer: B
V = 7576 m/s
Explanation: Given that the
circular radius R = 7,000,000 m,
The acceleration due to Earth's gravity is 8.2 m/s2
Let's use gravitational field strength formula to get the mass of the satellite.
g = Gm/R^2
Where G = 6.674×10^−11m3⋅kg−1⋅s−2
Substitutes all the parameters into the formula
8.2 = (6.674×10^-11 × M)/(7000000)^2
Cross multiply
4.018 × 10^14 = 6.674×10^−11M
Make M the subject of formula
M = 4.018 × 10^14 ÷ 6.674×10^−11
M = 6.02 × 10^24 kg
The Force of attraction experienced by the satellite will be
F = mg
F = 6.02 × 10^24 × 8.2
F = 4.94 × 10^25 N
But centripetal force is
F = MV^2/ R
Where V = velocity of the satellite
Substitute F, M and R into the formula
4.94×10^25 = (6.02×10^24V^2)/ 7 ×10^6
Cross multiply
3.46 × 10^32 = 6.02×10^24V^2
Make V^2 the subject of formula
V^2 = 3.46×10^32 ÷ 6.02×10^24
V^2 = 57403600.2
Find the square root of the value to get V
V = 7576 m/s
The required velocity of the satellite is 7576 m/s approximately
Question 1
a. Name each of the laboratory equipment labelled V to Z. (5 marks)
b. Mention one use of each of the laboratory equipment
identified in question 'a' above. (5 marks)
Answer:
a. All the laboratory equipment given are very basic equipment used in all the laboratories. Name of each equipment is as follows:
V refers to the tape measure.W refers to dropper.X refers to an inoculating loop.Y refers to a stopwatch.Z refers to the microscope.b. Use of each laboratory equipment identified is:
Tape measures (V) is used to measure the length of objects or distance in a laboratory.Dropper (W) is used to measure unit of drop required to dispensed as one drop or several drops in any experiment.Inoculating loop (X) is used by microbiologists to cultivate microbes on plates and retrieving an inoculum from a culture of microorganisms. Stopwatch (Y) is used to measure the time of any experiment.Microscope (Z) is used to magnify an object to look at it in detail.Please i need the answers now. a) Explain why i) More thermal energy is required to raise the temperature of 2 Kg of a substance by 10°C than is required to raise the temperature of 1 Kg of the same substance by 10°C. ii) A solid expand when heated.
Answer: find the answer in the explanation
Explanation:
1.) More thermal energy will be required to raise the temperature of 2 Kg of a substance by 10°C than is required to raise the temperature of 1 Kg of the same substance by 10°C.
Because the thermal energy depends on the mass of an object.
If the two materials are the same, then they will have the same specific heat capacity. Thermal energy can be expressed as:
H = MCØ
Where
M = mass of the body
C = specific heat capacity
Ø = change in temperature
H = thermal energy
If u substitute the two values of masses into the formula above, then, the mass of 2kg will produce higher thermal energy .
Il.) Heat causes expansion. Using kinetic theory to explain this, the molecules of solid material are in a fixed pattern, held together with strong bonds. When heat is applied to the solid, the molecules will start vibrating in their fixed position. As a result of this, the bond between the molecules begins to loss. This eventually lead to expansion of solid.
...............................................................help
Answer:
The maximum height that a cannonball fired at 420 m/s at a 53.0° angles is 5740.48m.
hmax = 5740.48 m
Explanation:
This is an example of parabolic launch. A cannonball is fired on flat ground at 420 m/s at a 53.0° angle and we have to calculate the maximum height that it reach.
V₀ = 420m/s and θ₀ = 53.0°
So, when the cannonball is fired it has horizontal and vertical components:
V₀ₓ = V₀ cos θ₀ = (420m/s)(cos 53°) = 252.76 m/s
V₀y = V₀ cos θ₀ = (420m/s)(cos 53°) = 335.43m/s
When the cannoball reach the maximum height the vertical velocity component is zero, that happens in a tₐ time:
Vy = V₀y - g tₐ = 0
tₐ = V₀y/g
tₐ = (335.43m/s)/(9.8m/s²) = 34.23s
Then, the maximum height is reached in the instant tₐ = 34.23s:
h = V₀y tₐ - 1/2g tₐ²
hmax = (335.43m/s)(34.23s)-1/2(9.8m/s²)(34.23s)²
hmax = 11481.77m - 5741.29m
hmax = 5740.48m
The fielder attempts to catch a second ball. Just before the fielder catches the ball, the air resistance acting on the ball is 1.2N. Calculate the resultant force acting on the ball. Remember to include its direction and the unit. Assume the ball is falling vertically
Answer:
Resultant force = (1.2 - 9.8m)ĵ N
where m = mass of the ball
Magnitude of the resultant force = (9.8m - 1.2) N
Since the weight of the ball is expected to exceed the air resistance (because the ball is falling vertically downwards), the direction of the resultant force is vertically downwards. Its unit is Newtons, the SI unit of Force.
Explanation:
If a ball is falling vertically downwards, the only two forces acting on the ball include the weight of the ball (the pull of gravity on the ball) and the air resistance on the ball.
Weight of the ball acts downwards and is given as mg. where m = mass of the ball and g is the acceleration due to gravity = 9.8 m/s²
W = mg = (9.8m) N
In vector form, W = (-9.8mĵ) N
The air resistance on the ball = 1.2 N, the air resistance acts in the direction opposite the motion of the ball, and since the ball is moving vertically downwards, the air resistance acts vertically upwards.
In vector form, the air resistance = (1.2ĵ) N
Hence, the resultant force acting on the ball is the vector sum of all the forces acting on the ball.
Resultant force = (-9.8mĵ) + (1.2ĵ)
= (1.2 - 9.8m)ĵ N
Since the weight of the ball is expected to exceed the air resistance (because the ball is falling vertically downwards), the direction of the resultant force is vertically downwards.
Hope this Helps!!!
An aluminum bar 600mm long, with diameter 40mm long has a hole drilled in the center of the bar.The hole is 30mm in diameter and is 100mm long. If modulus of elasticity for the aluminum is 85GN/m2.Calculate the total contraction on the bar due to a compressive load in 180KN
Answer:
Total contraction on the Bar = 1.22786 mm
Explanation:
Given that:
Total Length for aluminum bar = 600 mm
Diameter for aluminum bar = 40 mm
Hole diameter = 30 mm
Hole length = 100 mm
elasticity for the aluminum is 85GN/m² = 85 × 10³ N/mm²
compressive load P = 180 KN = 180 × 10³ N
Calculate the total contraction on the bar = ???
The relation used in calculating the contraction on the bar is:
[tex]\delta L = \dfrac{P *L }{A*E}[/tex]
The relation used in calculating the total contraction on the bar can be expressed as :
Total contraction in the Bar = (contraction in part of bar without hole + contraction in part of bar with hole)
i.e
Total contraction on the Bar = [tex]\dfrac{P *L_1 }{A_1*E} + \dfrac{P *L_2 }{A_2 *E}[/tex]
Let's find the area of cross section without the hole and with the hole
Area of cross section without the hole is :
Using A = πd²/4
A = π (40)²/4
A = 1256.64 mm²
Area of cross section with the hole is :
A = π (40²-30²)/4
A = 549.78 mm²
Total contraction on the Bar = [tex]\dfrac{P *L_1 }{A_1*E} + \dfrac{P *L_2 }{A_2 *E}[/tex]
Total contraction on the Bar = [tex]\dfrac{180 *10^3 \N }{85*10^3 \ N/mm^2} [\dfrac{500}{1256.64}+ \dfrac{100}{549.78}][/tex]
Total contraction on the Bar = 2.117( 0.398 + 0.182)
Total contraction on the Bar = 2.117*(0.58)
Total contraction on the Bar = 1.22786 mm
Which condition must be met in order for an equation to be balanced?
Answer:
There must be an equal amount of each element on both sides of the equation. Hope this helps and please marks as the brainliest.
Explanation:
Answer:
The answer is D
Explanation:
Hope this helps!
What is the velocity of an object that has been in free fall for 2.5
Answer: calculate the free fall distance and velocity without air resistance from, the free fall.
Explanation:
To find out something's speed (or velocity) after a certain amount of time, you just multiply the acceleration of gravity by the amount of time since it was let go of. So you get: velocity = -9.81 m/s^2 * time, or V = gt. The negative sign just means that the object is moving downwards
Electrons are emitted form a certain metal with a maximum kinetic energy of 2 eV when 6-eV photons are inicident on its surface. What is the maximum kinetic energy of electrons emitted if photons of twice the wavelength are inicdent on this metal? Explain your answer
Answer:
The energy of the light is not higher than the work function. Then, the electrons are not emitted.
Explanation:
In order to calculate the maximum kinetic energy of the electrons for photons of twice the wavelength of the light, you first calculate the wavelength of photons with energy of 6eV. You use the following formula:
[tex]E_p=h\frac{c}{\lambda}[/tex] (1)
c: speed of light = 3*10^8 m/s
λ: wavelength of the light
h: Planck's constant in eV.s = 4.135*10^-15 eV.s
E: energy of the photons = 6eV
You solve the equation (1) for λ:
[tex]\lambda=\frac{hc}{E}=\frac{(4.135*10^{-15}eV)(3*10^8m/s)}{6eV}\\\\\lambda=2.06*10^{-7}m[/tex]
Next, you calculate the energy of photons with twice the wavelength:
[tex]E_p'=h\frac{c}{2\lambda}=(4.135*10^{-15}eV)\frac{3*10^8m/s}{2(2.06*10^{-7}m)}\\\\E_p'=3.0eV[/tex]
Next, you calculate the work function of the metal by using the equation for the photo electric effect:
[tex]K=E_p-\Phi[/tex] (2)
Ф: work function
Ep: energy of the photons = 6eV
K: kinetic energy of emitted electrons = 2eV
You solve for Ф:
[tex]\Phi=E_p-K=6eV-2eV=4eV[/tex] (3)
Finally, you calculate the kinetic energy of the emitted electron by the metal when the light with energy Ep' is used:
[tex]K=E_P'-\Phi=3.0eV-4eV[/tex]
It is clear that for a light with energy 3.0eV has an energy lower than the work function of the metal, then, the electrons are not emmited by the metal
define hardware.Give 2 examples
Answer:
They are the physical parts of a computer.
examples :monitor,keyboard,system unit and mouse.
A car manufacturer wants to change its car’s design to increase the car’s acceleration. Which changes should the engineers consider making to the design?
Answer:
The car manufacturers could increase bore of the cylinders, place the engine in the center or back of the car, add 1 to 2 turbochargers, and lower the center of gravity of the vehicle to increase traction.
Explanation:
Turbochargers would be recommended because they significantly increase both the torque of the engine as well as the amount of horses powering the car while also increasing original efficiency both with and without the additional power. Weight adjustment allows for lightweight vehicles with good traction. This is important to both keep control of the car under acceleration, but it also makes the vehicle more efficient due to the now sheddable unnecessary weight. A more obvious approach would be to increase the base horsepower and torque of the engine by increasing the bore of the cylinders and the weight of the pistons. This acts as an inertial lever, because the extra piston weight will drag the crankshaft faster. This could also be achieved by taking away piston weight, but this could be catastrophic should a piston slip.
A force of 2500 N is exerted on a piston that has an area of 0.060 m2. What
force is exerted on a second piston that has an area of 0.18 m?
F F2
Α1, Α2,
Explanation:
SI LA PRESIÓN ES LA MISMA ENTONCES:
P = 2500 N/[tex]0.060 m^{2}[/tex] = 41667 Pa
F2 = 41667 Pa([tex]0.18 m^{2}[/tex]) = 7500 N
The force is exerted on a second piston will be 7500N.
What is pressure?The pressure is the amount of force applied per unit area.
Pressure p = Force/Area
Given is a force of 2500 N is exerted on a piston that has an area of 0.060 m². Area of the second piston is 0.18m².
The pressure will be same for both the piston
P1 =P2
F1/A1 = F2/A2
Put the values, we get
2500 /0.060 = F2/0.18
F2 = 7500 N
Hence, force exerted on the second piston is 7500 N.
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How to convert 200ml to m(3)?
sara walks part way around a swimming pool. she walks 50 yards north, then 20 yards east, then 50 yards south. the magnitude of her displacement during this walk is ______ yards
Answer:
+20 yards
Explanation:
Given:
North = 50 yards
East = 20 yards
South = 50 yards
Required
Calculate the magnitude of displacement
Displacement is a vector quantity and it is a measure of distance taken and the direction of the distance.
Take up directions as positive and down directions as negative.
Similarly, we'll take right direction as positive and left direction as negative.
We understand that;
North is upwards; so, the displacement is +50 yards
East is rightwards; so, the displacement is +20 yards
South is downwards; so the displacement is -50 yards
Hence, her total displacement is
Displacement = +50 yards + 20 yards - 50 yards
Displacement = +20 yards
Hence, Sara's displacement is +20 yards
Henri draws a wave that has a 4 cm distance between the midpoint and the trough. Geri draws a wave that has an 8 cm vertical distance from the bottom of the trough to the top of the crest. Which statement best describes the energy in Henri and Geri’s waves? Henri’s wave has a higher amplitude and more energy. Henri’s wave and Geri’s wave have the same amplitude and the same energy. Henri’s wave and Geri’s wave have the same amplitude, but Geri’s has more energy. Geri’s wave has a higher amplitude and more energy.
Answer:
Henri’s wave and Geri’s wave have the same amplitude and the same energy
Explanation:
The amplitude of a wave is the distance between the midpoint and the trough (or the crest). This is equivalent to half the distance between the trough and the crest. Therefore:
amplitude of Henri's wave: 4 cmamplitude of Geri's wave: 8/2 = 4 cmThe energy of a wave is directly proportional to its amplitude.
Answer:
its letter b
Explanation:
a material that is not a mixture; it has the same properties all the way through is called. Its 9 letters long and the second letter is u and the eighth letter is c. Its a crossword clue by the way
Answer: The material that is not a mixture; it has the same properties all the way through is called a substance.
Explanation:
A pure substance is a form of matter that has a constant composition and properties that are constant throughout the sample. Hence, it cannot be separated by physical means. Example: Gold
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present. They can be separated by physical means as well. Example: Air
Thus the material that is not a mixture; it has the same properties all the way through is called a substance.
The displacement from equilibrium of an oscillating weight suspended by a spring and subject to the damping effect of friction is given by y(t) = 2e−t cos 4t, where y is the displacement (in centimeters) and t is the time (in seconds). Find the displacement when t = 0, t = 1 4 , and t = 1 2 . (Round your answers to two decimal places.)
Note that the correct times are t = 0, t = 1/4, t = 1/2. You can tell from the spaces between the two digits. i.e 1&4 and 1&2
Answer:
y(0) = 2.00 cm
y(1/4) = 1.56 cm
y(1/2) = 1.21 cm
Explanation:
This is a very simple exercise, the displacement of the oscillating weight from equilibrium has already been modeled by the equation:
[tex]y(t) = 2e^{-t} cos 4t[/tex]
Where y = displacement ( in cm)
and t = time (in seconds)
The task is to find the displacement when t = 0, 1/4 and 1/2
When t = 0 s
[tex]y(0) = 2e^{0} cos 4(0)\\y(0) = 2* 1*1\\y(0) = 2.00 cm[/tex]
When t = 1/4 s
[tex]y(1/4) = 2e^{-1/4} cos 4(1/4)\\y(14) = 2e^{-1/4} cos (1)\\y(1/4) = 1.56 cm[/tex]
When t = 1/2
[tex]y(1/2) = 2e^{-1/2} cos 4(1/2)\\y(14) = 2e^{-1/2} cos (2)\\y(1/2) = 1.21 cm[/tex]
a man has a mass of 70kg. Calculate his weight on earth where the gravitational strength is 10 N/kg
Answer:
So the weight of the body is 700N
Explanation:
mass of the object=70kg
force of gravity=10N/kg
weight of the object=w-?
as we know that
weight=mass × force of gravity
weight=70kg × 10N/kg
WEIGHT OF THE BODY=700N
I HOPE IT WILL HELP YOU
GOOD LUCK FOR THE ASSIGNMENT
The correct answer is 700 N.
Object mass = 70 kg
Gravity = 10N / kg
Weight = Mass x Gravity
Weight = 70kg x 10N / kg
Weight = 700 N
What is the gravity for a mass of 10kg?Mass is more basic because it is a unique property of the object. Weight varies from place to place depending on the acceleration of gravity. If the mass on the earth is m = 10kg, the weight is W = mg = 10 x 10 = 100N.
The strength of the Earth's gravitational field is 10 Newtons (N / kg) per kilogram. This means that there is a force of 10 Newtons per kilogram on Earth. Mass is the amount of substance that makes up an object.
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A radioactive isotope has a half-life of 2 hours. If a sample of the element contains 600,000 radioactive nuclei at 12 noon, how many radioactive nuclei would be left at 6 pm?
Answer: There will be 75258 nuclei left at 6 pm.
Explanation:
a) half-life of the radioactive substance:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.69}{k}[/tex]
[tex]k=\frac{0.69}{t_{\frac{1}{2}}}=\frac{0.693}{2hours}=0.346hours^{-1}[/tex]
b) Expression for rate law for first order kinetics is given by:
[tex]A=A_0e^{-kt}[/tex]
where,
k = rate constant
t = time for decomposition = 6 hours ( from 12 noon to 6 pm)
A = activity at time t = ?
[tex]A_0[/tex] = initial activity = 600, 000
[tex]A=600000\times e^{-0.346\times 6}[/tex]
[tex]A=75258[/tex]
Thus there will be 75258 nuclei left at 6 pm.
Conductors and Insulators
Answer:
ConductorsThe substances which allow an electric current to pass through it is called conductors.
Example: Metals like copper,iron ,graphite etc.
InsulatorsThe substances which do not allow the electric current to pass through is called Insulators.
Example: Glass, dry wood ,plastic etc.
Hope this helps...
Good luck on your assignment...
Austin kicks a soccer ball with an initial velocity of 18.0 m/s at an angle of 35.0°. What are the horizontal and vertical components of the initial velocity? Round your answers to the nearest tenth. vix = m/s viy = m/s
Answer:
(vix, viy) = (14.7 m/s, 10.3 m/s)
Explanation:
The velocities of interest are ...
(vix, viy) = (vi)(cos(35°), sin(35°)) = (18 m/s)(cos(35°), sin(35°))
(vix, viy) = (14.7 m/s, 10.3 m/s)
Answer:
First one = 14.7
Second one = 10.3
Explanation:
EDGE
if a room is closed for 2-4 hours then when we open the door we need a little bit of more energy than the actual energy and feel someone is pushing the door from the back side . what is the reason behind it ? which force is that?
Answer:
The reason is because the pressure of the air inside the room drops with time which makes opening the door to require an increased amount of force to make up for the reduced pressure inside the room
Explanation:
From the kinetic theory of gases we have the following relation;
[tex]v_{rms} = \sqrt{\dfrac{3 \cdot K \cdot T}{m} }[/tex]
[tex]p = \dfrac{n \cdot MW \cdot v^2_{rms} }{3 \cdot V}[/tex]
Where:
K = Boltzmann constant
T = Temperature
m = Mass
MW = Molecular weight
V = Volume
[tex]v_{rms}[/tex] = Root mean square velocity
Whereby the room door is closed, the kinetic energy of the air particles will be used up such that the average velocity of the particles will decrease, given that the volume of the room is constant, the pressure inside the room will drop below the original pressure outside the room such that the force on the door due to the outside pressure is larger than the force on the door from inside the room requiring a larger amount of force to overcome the resistance of the now higher outside pressure force.
The density of pine is generally about 0.5 g/cm3. What is the mass of a 800 cm3 piece of pine
Answer:
400grams
Explanation:
Mass is density × volume
0.5×800= 400 grams
Mass is density × volume
0.5×800= 400 grams.
What does density mean?
Density is the number of things—which could be people, animals, plants, or objects—in a certain area. To calculate density, you divide the number of objects by the measurement of the area. The population density of a country is the number of people in that country divided by the area in square kilometers or miles.
How do we calculate density?
density, the mass of a unit volume of a material substance. The formula for density is d = M/V, where d is density, M is mass, and V is volume.
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A schooterist move along a circular path for radius 0.2km for 2 minutes
A ) what is the distance travelled
B) what is the velocity of the schooterist
Answer:
a 1.26 km b 10.5 m/s
Explanation:
A. Distance travelled by the schooterist
Since the schooterist travels in a circular path, the distance moved is the circumference of a circle, C with radius r = 0.2 km
C = 2πr
= 2π(0.2 km)
= 1.26 km
So, the distance travelled by the schooterist is 1.26 km
B. The velocity of the schooterist
The velocity of the schooterist v = distance travelled/time
distance travelled = 1.26 km = 1260 m
time = 2 minutes = 2 × 60 s = 120 s
So, V = 1260 m/120 s
= 10.5 m/s
So, the velocity of the schooterist is 10.5 m/s
Power stations do not work at maximum output all of the time. The capacity factor for non-renewables is always higher than for renewables. This is because...
Answer:
The answer is below
Explanation:
There are various reasons for a power station not to work at maximum output all the time. These includes technical constraints, such as
1. Availability of the plant: sometimes the availability of generating plants may affect capacity factor, which may be caused due to plant part break down, or routine servicing.
2. Economic reasons: the capacity factor of a generating plant can be affected due to the level of usage at peak performance, as the cost of running the plant at peak form may be expensive to maintain.
3. Availability of the energy resource: this often applicable to generating plants using renewable energy, this is because, energy source such as wind, solar and water may not be readily available all the year round as they can be seasonal. Also, the maximum output can be affected even if the generating plant is using non renewable energy, as there maybe some times, unavailability or low supply of the crude oil or fossil fuel.
Also, the main reason in which the capacity factor for non-renewables is always higher than for renewables, is because of the availability factor, or availability of the energy resources. This is because renewable energy such as water, wind, and solar are not readily available all the time, and are subject to atmospheric conditions, unlike non renewable energy such as crude oil, which can be readily available by purchasing them.
What is the speed of a car at rest?