Answer: Efficiency signifies a peak level of performance that uses the least amount of inputs to achieve the highest amount of output.
Explanation: It minimizes the waste of resources such as physical materials, energy, and time while accomplishing the desired output.
Answer:
The efficiency of a simple machine is defined as the ratio of useful work done by the machine ( output work) to the total work out into the machine ( input work).
Explanation:
EfficiencyIf a machine overcomes a load ' L ' and the distance travelled by the load is 'Ld' , the work done by the load is L× LD. It is also called output work or useful work.
Therefore, [tex] \boxed{Output \: work \: = L \: \times \: Ld}[/tex]
Likewise, The effort applied to overcome the load is 'E' and the distance covered by effort is 'Ed' , the work done by effort is E × Ed. It is also called input work.
Therefore, [tex] \boxed{Input \: work = E \times Ed}[/tex]
The efficiency of a simple machine is defined as the ratio of output work to the input work .
Therefore, [tex] \boxed{Efficiency ( η)= \frac{outpt \: work}{input \: work} \times 100\%}[/tex]
Efficiency is expressed in percentage. It is a ratio of two works. A machine is never 100% efficient. It is because no machine is friction free and due to friction, some of the input energy is wastes in the form of heat energy.
[tex] \mathrm{Hope \: I \: helped!}[/tex]
[tex] \mathrm{Best \: regards!}[/tex]
Millimeters, centimeters, meters,
kilometers, inches, feet, and
miles are all examples of
plz help
Millimeters, centimeters, meters, kilometers, inches, feet, and miles are all examples of unit of length like: distance between two points and displacement of any object.
What is unit?The quantity with a constant magnitude that is used to measure the magnitudes of other quantities of the same type is referred to as a unit in physics.The formula: physical quantity = numerical value × unit. can be used to determine a physical quantity's magnitude.A unit shouldn't alter as time or environmental factors like pressure and temperature change.It ought to be precisely defined.It need to be readily available and repeatable.Meter is a Si unit of length whereas centimeter is CGS unit of length and Feet is FPS unit of lengths. Another units are also useful in measuring lengths.
Learn more about units here:
https://brainly.com/question/12750330
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A series combination of 12 Ω and 3 Ω is connected in parallel with another series combination of 6 Ω and 3 Ω. If a potential difference of 4 V is applied across it find the i) current is drawn from the battery ii) current through 12 Ω resistor (iii)potential difference across 6 Ω resistor?
Answer:
a) 0.73A
b) 0.23A
c) 2.76V
Explanation:
We need to first resolve the two resistors in series. The resistors in series are
12 Ω and 3 Ω AND 6 Ω and 3 Ω
For 12 Ω and 3 Ω in series, total effective resistance = 12 Ω + 3 Ω = 15 Ω
For 6 Ω and 3 Ω in series, total effective resistance = 6 Ω + 3 Ω = 9 Ω
Since the equivalent series resistors i.e 15Ω ND 9Ω are connected in parallel, the total effective resistance Rt will be expressed as;
1/Rt = 1/15+1/9
1/Rt = (3+5)/45
1/Rt = 8/45
Rt = 45/8 Ω
a) If a potential difference of 4 V is applied across it, the total current I in the circuit can be derives using the ohms law.
According to the law E = IRt
Given E = 4V, Rt = 45/8
I = E/Rt
I = 4/(45/8)
I = 4 * 8/45
I = 32/45
I = 0.73A
Hence, the current drawn from the battery is 0.73A
b) Before we can calculate the current in the 12Ω resistor, we need to calculate the current in the equivalent resistance of 15Ω(sum of 12Ω and 3Ω)
Current in the 15Ω resistor = Voltage across the 15Ω resistor/Resistance
Current in the 15Ω resistor = 4/15
Current in the 15Ω resistor = 0.27A
Since the same current flows in a series connected resistors, hence the correct in the 12ohms resistor is also 0.27A.
c) Before we can calculate the pd across the 6ohms resistor, we need to know the voltage across the effective resistance of 9ohms(6ohms+3ohms). The pd across the 9ohm resistance will be the same as the source voltage i.e 4Volts.
We will need to share this 4volts between the 6ohms and the 3ohms using ohms law.
According to the law, V = IR
For the 6ohms resistor, voltage across it will be;
V = (0.73-0.27)×6
V= 0.46×6
V = 2.76Volts.
Hence the voltage across the 6ohms resistor is 2.76V.
The law of conservation of momentum states that the total momentum of interacting objects does not _____. This means the total momentum _____a collision or explosion is equal to the total momentum _____ a collision or explosion.
Answer:
The law of conservation of momentum states that the total momentum of interacting objects does not change. This means the total momentum before a collision or explosion is equal to the total momentum after a collision or explosion.
Answer:
The answer is
Explanation:
Change. Does not change.means.
Hope this helps....
Have a nice day!!!!
given that the amplitude of the scattered light is (1) directly proportional to that of incident light (2) directly propotional to the volume of the scattering dust particles (3)inversely proportional to its distance from the scattering particles and (4) dependent upon the wavelength of the light. show that the intensity of scattered light varies as 1/wavelength^4
Answer:
The correct answers are 2, 4
Explanation:
The dispersion of light occurs due to the interaction of electromagnetic radiation with matter, let's analyze the phenomenon, when a ray of light reaches a particle is absorbed and subsequently re-emitted in all directions, for radiation of lower wavelength (higher frequency ) the highest absorptions and therefore the missionary also the highest; An example of this is the blue light from the atmosphere, which is the absorption of blue light and its subsequent re-emission
Based on this explanation, the dispersion in gas particles or molecules is proportional to the frequency of the light (inversely proportional to the wavelength) and is also proportional to the number of dispersing particles in the air, that is, to the total volume of the particles. dispersers.
The correct answers are 2 and 4
On the graph of voltage versus current, which line represents a 2.0 resistor?
Answer:
answer is B
Explanation:
Acc. to Ohm's Law:
V = I.R and therefore R=( V/I )
For line A, R = 6/2 = 3
line B, R = 4/2 = 2 ( for all the points plotted on this line the ratio of V and I is 2)
Line C = 2/2 = 1
Line D < 1
Hence, the correct answer is Line B :-)
Question 14 of 30
A bundle of roofing shingles slides off a roof and is falling to the ground. As it
falls, what kind of energy does it possess?
O A. Kinetic only
O B. Potential only
O C. Radiant
D. Kinetic and potential
Answer:
kinetic and potential
A particular celestial body orbits at a particular speed. For every two orbits it makes, another celestial body orbits three times. This orbital resonance would correspond to which musical interval?
Answer:
Explanation:
frequency of first body f₁ = 2 / T where T is time taken by it for making two orbits
frequency of second body f₂ = 3 / T
ration of two frequency
f₁ / f₂ = 2 / 3
This ratio is called perfect fifth in musical interval .
The velocities of light in air and glass are 3.0 x 10^8ms and 2.0×10^8ms respectively. If the angle of refraction is 30°, the sine of the angle of incidence is?
Pls help
Answer:
0.75
Explanation:
[tex]refractive \: index \: = \frac{3.0 \times {10}^{2} }{2.0 \times {10}^{2} } [/tex]
= 1.5
[tex]refractive \: index = \frac{ \sin(angle \: of \: incidence) }{ \sin(angle \: of \: refraction) } [/tex]
[tex]1.5 = \ \frac{ \sin(i) }{ \sin(30) } [/tex]
1.5 × ½ = sin(i)
[tex] \sin(i) = 0.75[/tex]
What is the electric force acting between two charges of 0.0072 C and -0.0060 C that are 0.0040 m apart?
Answer:
Fe = 2.4 × 10^10 N
Explanation:
Given the following :
q1 = charge 1 = 0.0072 C = positive direction
q2 = charge 2 = 0.0060 C = - ve direction
r = distance = 0.0040
Using the relation :
Fe = K(q1q2) /r^2
Where K = columb's constant = 9×10^9 Nm^2/C^2
Fe = electric force
Fe = 9×10^9(0.0072 * 0.0060) / 0.0040^2
Fe = [9×10^9 (0.0000432)] / 0.000016
Fe = 388,800 / 0.000016
Fe = 24300000000
Fe = 2.43 × 10^10 N
Which of the following will cause an induced current in a coil of wire? A. A wire carrying a constant current near the coil B. A magnet being moved into or out of the coil C. The constant field of the Earth passing through the stationary coil D. A magnet stationary resting near the coil
Answer:
B. A magnet being moved into or out of the coil
Explanation:
Faraday law of electromagnetic induction states that when there is change in flux , an emf is produced . Among the given instances , only in case of B , flux is changing . So current will be induced in the coil . We shall see how it takes place .
A wire carrying constant current will produce magnetic flux in nearby coil but there is no change in flux because current as well as position of wire with respect to coil are not changing .
Passing of magnetic field through a stationary coil produces flux in the coil but here too there is no change in flux so no current will be induced .
A magnet positioned near a coil creates magnetic flux in the coil but the magnitude of flux remains constant so no change in flux and no creation of induced current .
if a direction is somewhere between North and East it is measured in _____?
Answer:
degrees
Explanation:
If a direction is somewhere between north and east, it is measured in degrees.
This measurement will be possible thanks to the existence of geographical coordinates that are some 'imaginary lines' that help us find our location on the earth's surface. These lines are called latitude and longitude, both of which are measured in degrees.
It is like a sea battle game where you have to combine the rows and columns in order to identify where the targets are located. Geographic coordinates work the same way, you must combine the rows and columns of the planisphere to identify the locations of the planet. So the lines would be the latitudes and the columns the longitudes.
Which is the SI symbol for volume? m g L K
Common symbol of the volume (L)
Answer:
the answer is c.L
Explanation:
A cell membrane has a thickness of about 7 nm. How many cell membranes would it take to make a stack 2.3 in high?
Answer:
There are 8345714 cell membranes.
Explanation:
It is given that,
The thickness of a cell membrane is 7 nm
We need to find the number of cell membranes would it take to make a stack 2.3 inches high.
Firstly, the units must be same i.e. converting 2.3 inches to m
1 inch = 0.0254 m
2.3 inches = 0.05842 m
Let there are n number of cell membranes. So,
[tex]n=\dfrac{\text{stack height}}{\text{1 membrane thickness}}\\\\n=\dfrac{0.05842}{7\times 10^{-9}}\\\\n=8345714.28[/tex]
or
n = 8345714 cell membranes
i) A 100 W and 60 W bulb are joined in series and connected to the mains. Which bulb
will glow brighter? Why?
ii) A 100 W and a 60 W bulb are joined in parallel to the mains. Which bulb will
glow brighter? Why?
Answer:
i) 60 W
ii) 100 W
Explanation:
In each case, the bulb that dissipates the most power is the bulb that glows brighter. Power is voltage times current (P = VI). Using Ohm's law, we can rewrite this as P = I²R or P = V²/R.
Bulbs are rated at a certain power for a certain voltage. P = V²/R, so the bulb with the lower resistance will have the higher power rating. Therefore, the 100 W bulb has a lower resistance than the 60 W bulb.
i) They are in series, so they have the same current. P = I²R, so the bulb with the higher resistance will glow brighter. That's the 60 W bulb.
ii) They are in parallel, so they have the same voltage. P = V²/R, so the bulb with the lower resistance will glow brighter. That's the 100 W bulb.
A drone has been designed that can do monitoring and surveillance at considerable heights due to its light weight of 0.800 kg. For this purpose, they are doing a test to determine its maximum height and they make it start in a vertical direction, using its thrusters it manages to achieve a thrust of 35.0 N during the first 6.00 s. until the battery runs out. What was the maximum height that the drone reached?
Answer:
2660 m
Explanation:
Sum of the forces in the first 6.00 s:
∑F = ma
F − mg = ma
35.0 N − (0.800 kg) (10 m/s²) = (0.800 kg) a
a = 33.75 m/s²
The height it reaches during this time is:
Δy = v₀ t + ½ at²
Δy = (0 m/s) (6.00 s) + ½ (33.75 m/s²) (6.00 s)²
Δy = 607.5 m
The velocity it reaches is:
v = at + v₀
v = (33.75 m/s²) (6.00 s) + 0 m/s
v = 202.5 m/s
After the battery runs out, the drone is in free fall. At the highest point, the velocity is 0. The height at this point is:
v² = v₀² + 2aΔy
(0 m/s)² = (202.5 m/s)² + 2 (-10 m/s²) (h − 607.5)
h ≈ 2660 m
Help uhh i need to know this answer
Answer:
Explanation:
2. 330.63 ft because v*t=d and 3.09*107=330.63
3. 4.2 because 10/2.4=4.1666
4. 130 miles because 2 hours times 65mph= 130
5. 62.3 seconds because 480000/7700=62.33766233
8. 60 meters, because 0.5 *120 (because 2 minutes converted to seconds is 120) is equal to 60.
a 2-n force is applied to a spring, and there is displacement of 0.4 m. how much would the spring be displaced if a 5-n force was applied?
Answer:1m
Explanation:
2n=0.4m
5n=?
5n×0.4/2n=1m
What does the cross sign in the middle mean???
it is called the proportionality sign.
read as
"R is proportional to l"
IMPORTANT 3 QUESTIONS!
Answer:
7. 20,000,000 mL.
8. 8,000 m.
9. 120,000 secs.
10. 4
Explanation:
7. Determination of the volume in millilitres (mL)
Volume in litre (L) = 20,000 L
Volume in millilitres (mL) =..?
The volume in mL can be obtained as follow:
1 L = 1,000 mL
Therefore,
20,000 L = 20,000 x 1,000 = 20,000,000 mL.
Therefore, 20,000 L is equivalent to 20,000,000 mL.
8. Determination of the distance in metre (m)
Distance in mile = 5 mile
Distance in metre =?
First, we shall convert from mile to kilometre.
This can be done as follow:
1 mile = 1.6 km
Therefore,
5 mile = 5 x 1.6 = 8 km
Finally, we shall convert 8 km to metre (m).
This is illustrated below:
1 km = 1,000 m
Therefore,
8 km = 8 x 1,000 = 8,000 m
Therefore, 5 miles is equivalent to 8,000 m.
9. Determination of the time in seconds.
Time = 400 minutes for 5 days.
First, we shall convert 400 mins to hour.
This is illustrated below:
60 minutes = 1 hour
Therefore,
400 mins = 400/60 = 20/3 hours
The time (hours) is 20/3 hours in 1 day.
Therefore, the time (hours) in 5 days will be = 20/3 x 5 = 100/3 hours.
Next, we shall convert 100/3 hours to minutes.
This is illustrated below:
1 hour = 60 minutes
Therefore,
100/3 hours = 100/3 x 60 = 2000 mins
Finally, we shall convert 2000 mins to seconds.
This is illustrated below:
1 mins = 60 secs
2000 mins = 2000 x 60 = 120,000 secs.
Therefore, the time is 120,000 secs.
10. Determination of the number of significant figures.
To obtain the significant figures of a number, we simply count all the numbers available.
Therefore, the number of significant figures for 9876 is 4.
A dog is 10 m from a cat, whose speeds are 6 and 5 m / s, respectively. What time does the dog require to catch the cat?
Answer:
10 seconds
Explanation:
because the cat is moving one m/s slower than the dog, the dog has a relative speed of 1 m/s. 10 meters would take 10 seconds for the dog to cover
with solutions please give with solution
if u give me with solution I will mark in brainlist
Answer:
Magnitude of Force : 0.8 N
Explanation:
We know that the velocity of this particle changes from 15ms⁻¹, or in other words 15m / s, to the respective velocity 25m / s over the course of 2.5 seconds. Given this information we can determine the acceleration of the particle,
a = v₁ - v₂ / t = 25 - 15 / 2.5 = 10 / 2.5 = 4m / s²
Knowing the acceleration we can calculate the magnitude of the force using the formula f = ma - Newton's second law of motion,
f = m [tex]*[/tex] a = 200g [tex]*[/tex] 4m / s² = 800 g [tex]*[/tex] m / s²
Remember however that Newtons are in the standard units kg [tex]*[/tex] m / s². Therefore we have to convert 800 g to kg to receive our solution,
800 g = 800 / 1000 kg = 0.8 kg,
Magnitude of Force = 0.8 N ; Solution = Option B
element X has two isotopes: X-27 and x-29. x-27 has an atomic mass of 26.975 and a relative abundance of 82.33%, and X-29 has an atomic mass of 29.018 and a relative abundance of 17.67%. calculate the atomic mass of element X. show your work
Answer:
27.34 (no unit)
Explanation:
26.975*82.33%+29.018*17.67%
=27.34
1. If a car travels 400m in 20 seconds how fast is it going?
2. If you move 50 meters in 10 seconds, what is your speed?
3. You arrive in my class 45 seconds after leaving math which is 90 meters away. How fast did you travel?
4. A plane travels 395,000 meters in 9000 seconds. What was its speed?
5. It takes Serina 0.25 hours to drive to school. Her route is 16 km long. What is Serina's average speed on her
drive to school?
Answer:
1) 20 m/s
2) 5 m/s
3) 2 m/s
4) 395,000m/9000s
5) 16 km/0.25h
Explanation:
i dunno
Using examples, explain why the first and second Newton laws of motion are significant for living organisms.
Answer:
1) Newton's first law of motion states an object will remain at rest or in uniform will be in uniform motion in a straight line unless a force acts on it
2) Newton's second law states the acceleration of an object is directly proportional to the applied force acting on an object and inversely proportional to the mass of the object
Explanation:
1) With Newton's first law, we are able arrange things within a space and schedule meetings in time knowing that they will remain in place unless an external force changes their positions
2) An example of Newton's second law of motion is that small objects such as a ball are easily accelerated and can be given appreciable acceleration for flight by single, one time contact (such as kicking the ball) while larger objects such as a rock require sustained force application to change their location.
Select the correct answer. x y 2.5 6.25 9.4 88.36 15.6 243.63 19.5 380.25 25.8 665.64 The table lists the values for two parameters, x and y, of an experiment. What is the approximate value of y for x = 4? A. 11 B. 16 C. 24 D. 43
Answer: B. 16
Explanation:
The given table:
x y
2.5 6.25
9.4 88.36
15.6 243.63
19.5 380.25
25.8 665.64
Here, we observed that value of y is the square value of x.
i.e. [tex]y=x^2[/tex] [For example 2.5²=6.25, 9.4²=88.36, 15.6²=243.63]
Put x=4, we get
[tex]y=4^2=16[/tex]
Hence, the approximate value of y for x = 4 is 16.
So, the correct option is B. 16 .
Answer:
The answer is A.
Explanation:
Will mark as BRAINLIEST.......
The position vector is given by vector r= 5t² I cap + 2 t³ j cap + 2 k cap. Find it's velocity and acceleration at t=2s.
Answer:
We have the position vector given in terms of time t. r(t) = t^3*i + t^2*j
To find the velocity vector we have to differentiate r(t) with respect to time.
r'(t) = 3t^2*i + 2t*j
The vector representing acceleration is the derivative of the position vector
r''(t) = 6t*i + 2*j
When time t = 2.
The velocity vector is 3*2^2*i + 2*2*j
=> 12*i + 4*j
The speed is the absolute value of the velocity vector or sqrt(12^2 + 4^2) = sqrt (144 + 16) = sqrt 160
The acceleration vector is 6*2*i + 2*j
=> 12*i + 2*j
The required acceleration at t=2 is 12*i + 2*j and the speed is sqrt 160.
Explanation:
Can I have thx and brainliest?
Please give best dialogue in photo that is attached And you are marked as Brainliest
Answer:
The correct answer is
Explanation:
Character 1: Why are these comic books so hard to read? Can u read them?
Character 2: No it's easy to read Tigger. It's because you are an animal an I am a human being. U don't know how to read.
Hope this helps....
Have a nice day!!!!
Answer:
Dialogue 1:
Hey buddy! Can you tell me what is written in this book? Its really hard to read:(
Dialogue 2:
Yeah! Its a story about a friendly tiger! And it is hard for you to read cause you don't know how to read.
Tip:
Try to make it more engaging :)
What is the cat's displacement t=0.5s to 1.5s,
Answer:
3.75m
Explanation:
area under graph
5+2.5=7.5
7.5/2=3.75
3.75x0.5=1.875
1.875x2=3.75m
The particles of a GAS within a closed container will collide with the container walls, exerting a FORCE. The force per unit of AREA is known as what?
Answer:
Pressure
Explanation:
One of the theories propounded by the Kinetic molecular theory, and which also provides an explanation of the several gas laws, is the statement that the gas molecules in a container, travel in straight lines and are in constant collision with themselves and the walls of the container, thus exerting force. This force is the pressure which is defined as the force per unit area.
There is no loss of energy in the collisions involving the gas molecules and that is why their movement can be described as elastic. The descriptions of the behavior of gas molecules in the Kinetic Molecular Theory, give rise to Charles law, Boyle's Law, Avogadro's Laws, Dalton's Law, and Amonton's Law.
Answer:
The pressure
Explanation:
Molecules of gases are constantly in motion, colliding with the walls of their container. This constant collision impacts force on the walls of the container, which depends on the speed with which the molecules are moving. The speed with which these molecules travel depends on the average kinetic energy of the molecules, which is proportional to the temperature.
This force when exerted per unit area is the pressure the gases exert on the walls of the container.
An ideal gas is enclosed in a piston-cylinder apparatus with the piston being freely movable. Given that LaTeX: \DeltaΔE is positive and LaTeX: \DeltaΔH is negative following a process, ____ the system absorbs heat and expands during the process. the system absorbs heat and contracts during the process. the system loses heat and expands during the process. the system loses heat and contracts during the process. the system loses heat but neither expands nor contracts during the process.
Clear question is;
An ideal gas is enclosed in a piston-cylinder apparatus with the piston being freely movable. Given that ΔE is positive and ΔH is negative following a process,
pick one
A) the system absorbs heat and expands during the process.
B) the system absorbs heat and contracts during the process.
C) the system loses heat and expands during the process.
D) the system loses heat and contracts during the process.
E) the system loses heat but neither expands nor contracts during the process.
Answer:
Option A is correct.
Explanation:
In thermodynamics, when the change in energy which is ΔE of a system is positive, it means that the system is undergoing an endothermic process. An endothermic process is simply one where heat is absorbed from the surroundings
Now, when change in enthalpy which is ΔH is negative, it means that it's an exothermic reaction. Exothermic means it releases heat to the surroundings. This means work is positive because the system does work on the surroundings. Thus it will expand.
So the correct answer is;
heat is absorbed from the surroundings and will expand during the process.
