Answer:
[tex]8.0\; \rm J[/tex].
Explanation:
The efficiency of a machine is the ratio between the useful output and the energy input:
[tex]\begin{aligned}\text{efficiency} &= \frac{\text{useful output}}{\text{energy input}} \times 100\%\end{aligned}[/tex]
Rearrange this equation to find energy input in terms of efficiency and useful output:
[tex]\displaystyle \text{energy input} = \frac{\text{useful output}}{\text{efficiency} / (100\%)}[/tex].
Substitute in the values: [tex]\text{useful output} = 1.2\; \rm J[/tex] and [tex]\text{efficiency} = 15\%[/tex]. Evaluate to find the value of [tex]\text{energy input}[/tex]:
[tex]\begin{aligned} \text{energy input} &= \frac{\text{useful output}}{\text{efficiency} / (100\%)} \\ &= \frac{1.20\; \rm J}{15\% / (100\%)} \\ &= 8.0\; \rm J\end{aligned}[/tex].
(Rounded to two significant figures as in the value of efficiency.)
Analyze the effects on a passenger riding in a car traveling at
50 km/h that collides head-on with a solid object.
Without:
The passenger will get seriously injuredColliding with the windshield at 50km/hCould result in deathWith safety:
The seatbelt holds tge passengers body back so they dont collide with anythingTheir head is cushioned by the airbagThe passenger might get minor injuries but nothing serious will happenWhat happens if you drop a chicken wing from the top of the Eiffel Tower
Answer:
I think it will brake or squashed
easy one - giving brainly if correct.
Gas.
HOPE YOU GET 100!
a gas increases in pressure from 2.00 atm to 6.00 atm at a constant volume of 1.00 m3 and then expands at constant pressure to a volume of 3.00 m3 before returning to its initial state as shown in the figure below. how much work is done in one cycle?
The work done on the given gas in one cycle is -405.3 kJ.
The given parameters;
initial pressure of the gas, P₁ = 2 atmfinal pressure of the gas, P₂ = 6 atminitial volume of the gas, V₁ = 1 m³final volume of the gas, V₂ = 3 m³Convert the pressure to Pascal (N/m²);
1 atm = 101325
The work done in one cycle is the area of the triangle and it is calculated as follows
[tex]Area = \frac{1}{2} \times base \times height\\\\Area = \frac{1}{2} \times (3 \ m^3\ -\ 1 \ m^3)\times (6 \ atm \ - \ 2 \ atm)\\\\Area = 4 \ atm -m^3\\\\Area = 4 \ atm -m^3 \ \times \frac{101325 \ Pa}{1 \ atm} \\\\Area = 405,300 \ m^3.Pa\\\\Area = 405,300 \ m^3. (N/m^2)\\\\Area = 405,300 \ Nm\\\\Area = 405,300 \ J\\\\Area = 405.3 \ kJ[/tex]
the net work done on the gas = - 405.3 kJ
Thus, the work done on the given gas in one cycle is -405.3 kJ.
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The mercury in a barometer of a cross-sectional area 1 cm² stands at 75 cm, and the space above it is 9 cm in length. What
volume of air, measured at 3. The mercury in a barometer of a cross-sectional area 1 cm² stands at 75 cm, and the space above it is 9 cm in length. What
volume of air, measured at atmospheric pressure, would have to be admitted into the space to cause the column of the mercury
to drop to 59 cm?
The ideal gas equation and the pressure in barometer allows us to find the amount of air that we must introduce into the barometer for the change in height of the mercury column is:
The variation of the volume is: ΔV = 7.67 cm³
Pressure is defined by the relationship between force and area.
P = F / A
The ideal gas equation establishes a relationship between pressure, volume, and temperature of an ideal gas.
PV = nR T
Where P is pressure, V is volume, and T is temperature.
Let's write this equation for two points assuming that the temperature has not changed.
P₀ V₀ = P₁ V₁
V₁ = [tex]\frac{P_o}{P_1} \ V_o[/tex] (1)
The subscript "o" is used for the start point and the subscript "1" for the end point.
The pressure in a barometer is:
P = ρ g y
They indicate the initial height of the barometer y₀=75 cm, the distance from empty space y'₀ = 9 cm and the final height of the barometer y₁ = 59 cm.
The volume of the cylinder is
V = π r² y
Let's calculate the initial volume.
V₀ = π 1 9
V₀ = 28.27 cm³
We substitute in equation 1.
V₁ = [tex]\frac{\rho \ g \ y_o}{\rho \ g \ y_1} \ V_o[/tex]
V₁ = [tex]\frac{y_o}{y_1} \ V_o[/tex]
Let's calculate.
V₁ = [tex]\frac{75}{59} \ 27.27[/tex]
V₁ = 35.94 cm³
The volume to be incremented is
ΔV = V₁ - V₀
ΔV = 35.94 - 28.27
ΔV = 7.67 cm³
Using the ideal gas equation and the pressure in barometer we can find the amount of air that we must introduce into the barometer for the change in height of the mercury column is:
The change of the volume is: ΔV = 7.67 cm³
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Without friction, what is the mass of an ball accelerating at 1.8 m/sec2 to which an
an unbalanced force of 42 Newtons has been applied?
A 75.60 kg
B 00.04 kg
C 23.33 kg
D 43.80 kg
Answer:
23.33 kgExplanation:
The mass of the object can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{42}{1.8} = 23.3333... \\ [/tex]
We have the final answer as
23.33 kgHope this helps you
Answer:
[tex]\boxed {\boxed {\sf C. \ 23.33 \ kg}}[/tex]
Explanation:
According to Newton's Second Law of Motion, force is the product of mass and acceleration.
[tex]F=ma[/tex]
The mass of the ball is unknown. The ball is accelerating at 1.8 meters per second squared. An unbalanced force of 42 Newtons is applied to the ball.
Convert the units of force. 1 Newton is equal to 1 kilogram meter per second squared, so our answer of 42 Newtons is equal to 42 kg*m/s².
F= 42 kg*m/s² a= 1.8 m/s²Substitute the values into the formula.
[tex]42 \ kg*m/s^1 = m * 1.8 \ m/s^2[/tex]
We are solving for the mass, so we must isolate the variable m. It is being multiplied by 1.8 meters per second squared. The inverse operation of multiplication is division. Divide both sides by 1.8 m/s².
[tex]\frac {42 \ kg*m/s^2}{1.8 \ m/s^2} = \frac{a*1.8 \ m/s^2}{1.8 \ m/s^2}[/tex]
[tex]\frac {42 \ kg*m/s^2}{1.8 \ m/s^2} =m[/tex]
The units of meters per second squared cancel.
[tex]\frac {42 \ kg}{1.8 } =m[/tex]
[tex]23.3333333 \ kg=m[/tex]
Round to the hundredth place. The 3 in the thousandth place tells us to leave the 3 in the hundredth place.
[tex]23.33 \ kg \approx m[/tex]
The mass of the ball is approximately 23.33 kilograms.
If you double the pressure of a constant amount of gas at a constant temperature, what happens to the volume
Answer: if you double the pressure, you will halve the volume. If you increase the pressure 10 times, the volume will decrease 10 times.
Explanation:
I need help in question 7, a and b.
Answer:
The graph for 7a is shown in the attachment. For question 7b she walks a distance of 16 meters. (m)
Explanation:
Describe the steps in solving the problem below.
A red cart of mass 4 kg slides to the right on a frictionless track with a velocity of +4 m/s. It collides with the stationary blue cart of mass 1 kg. After the collision, the blue cart has a velocity of +8 m/s. Calculate the velocity of the red cart after the collision. ;)
The velocity of the red cart after the collision is 2 m/s
From the law of conservation of momentum, initial momentum of system = final momentum of system.
m₁v₁ + m₂v₂ = m₁v₃ + m₂v₄ where m₁ = mass of red cart = 4 kg, v₁ = velocity of red cart before collision = + 4 m/s, v₃ = velocity of red cart after collision, m₂ = mass of blue cart = 1 kg, v₂ = velocity of blue cart before collision = 0 m/s (since it is initially at rest) and v₄ = velocity of blue cart after collision = + 8 m/s.
Substituting the values of the variables into the equation, we have,
m₁v₁ + m₂v₂ = m₁v₃ + m₂v₄
4 kg × 4 m/s + 1 kg × 0 m/s = 4v₃ + 1 kg × 8 m/s
16 kgm/s + 0 kgm/s = 4v₃ + 8 kgm/s
16 kgm/s = 4v₃ + 8 kgm/s
16 kgm/s - 8 kgm/s = (4 kg)v₃
(4 kg)v₃ = 8 kgm/s
Divide both sides by 4 kg, we have
v₃ = 8 kgm/s ÷ 4 kg
v₃ = 2 m/s
The velocity of the red cart after the collision is 2 m/s.
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What symbols are these?
Answer:
the bottom one is wollsiegel
Scientists are experimenting with a kind of gun that may eventually be used to fire payloads directly into orbit. In one test, this gun accelerates a 5.6-kg projectile from rest to a speed of 3.5 × 103 m/s. The net force accelerating the projectile is 2.5 × 105 N. How much time is required for the projectile to come up to speed?
Answer:
7.84 s
Explanation:
Ok, one step at a time. We know the mass of the projectile, we know the force. Acceleration is easily obtained from Newton second law:
[tex]\vec F = m\vec a[/tex][tex]2.5\times 10^5 = 5.6a \rightarrow a = (2.5/5.6) \times 10^5 = 4.46 \times 10^4 ms^-^2[/tex].
At this point, we know the acceleration, we know initial and final velocity, we can time the ammount of time it took to get there.
[tex]v= v_0 +at \rightarrow 3.5\times10^3 = 0 + 4.46\times10^4 t\\t= \frac{3.5\times10^3}{4.46\times10^4} = 7.84 s[/tex]
Calculate torque using angular momentum
Answer:
The equation net τ=ΔLΔt net τ = Δ L Δ t gives the relationship between torque and the angular momentum produced.
What’s the mass of the continent?
Answer:
Assume that the north american continent can be respanterd by a slab of rock 4000 km on a side and 30 km deep and that the rockiam help for youthankscommentflowingAlejandro Kirk is the catcher for the Blue Jays’ baseball team. He exerts a forward force on the 0.145-kg baseball to bring it to rest from a speed of 38.2 m/s. During the process, his hand recoils a distance of 0.135 m.
Determine is the acceleration of the ball.
Determine the force applied by Alejandro.
The kinematics and Newton's second law allow to find the results for the questions about the motion of the ball are:
The acceleration is: a = 5.4 10³ m / s² The force is: F = 7.84 10² N
Given parameters
Mass of the ball m = 0.145 kg Ball starts speed vo = 38.2 m / s Setback distance x = 0.135 mTo find
Acceleration The force
Kinematics studies the movement of bodies, looking for relationships between the position, speed and acceleration of bodies.
v² = v₀² - 2 ax
Wher vo es la initial veloicity, a the acceleration y x is the distance,
When the ball stops the velocity is zero.
0 = v₀² - 2ax
a = [tex]\frac{v_o^2}{2x}[/tex]
Let's calculate
a = [tex]\frac{38.2^2}{2 \ 0.135}[/tex]
a = 5.4 10³ m / s²
Newton's second law establishes a relationship between force, mass, and acceleration of the body.
F = ma
F = 0.145 5.4 10³
F = 7.84 10² N
In conclusion using kinematics and Newton's second law we can find the results for the questions about the motion of the ball are:
The acceleration is: a = 5.4 10³ m / s² The force is: F = 7.84 10² N
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Which of toby's answers is a correct description of what happens when a 1-kg cart traveling at 1 m/s collides inelastically with another 1-kg cart at rest?.
Answer:
hi I don't know sorry sorry forgive me
Explanation:
sorry
. Quỹ đạo chuyển động của một vật là
Answer:
you are very kind Po lang
How fast is an object going if it travels from San Diego to Anaheim in 1.25 hours (hr)? The distance from San Diego to Anaheim is 93 miles (mi).
a) 74.4 mi/hr
b) 116.25 mi/hr
c) 0.013 mi/hr
d) 84.25 mi/hr
e) None of the answers
Answer:
74.4 mph
Explanation:
Since we have the distance in miles and the time it took in hours, we can divide the two to get miles per hour.
speed = mi/hr
speed = 93/1.25
speed = 74.4 mph
Which of the following is NOT true of a hotspot?
Given what we know about hotspots and their characteristics, we can confirm that the option that is false regarding hotspots is "A. Hotspots are constantly moving forming chains of volcanoes".
In regards to the study of geology, we refer to hotspots as spots in an oceanic mantle where magma located below causes them to become intensely hot. This heat forces magma and therefore the mantle itself upwards as a tectonic plate moves across the spot, and therefore results in the formation of volcanic chains. Some very popular examples of volcanoes and volcanic islands formed by this method include:
Yellowstone National ParkHawaiiThe country of IcelandDespite the other options being true, option A is false given that hotspots are stationary elements of the oceanic mantle. Although some scientists believe that there is evidence of the movement of hotspots, this movement is slow enough to not be taken into account.
This question was answered in regards to the complete question found online which states:
Which of the following is NOT TRUE about hotspots? a. Hotspots are constantly moving forming chains of volcanoes.
b. Hotspots are stationary.
c. Hotspots form volcanic island arcs
d. Hotspots lie along an oceanic plate
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Estimate under what set of conditions it is possible, despite the spherical shape of the working electrode, to use linear diffusion equations to theoretically predict the current vs voltage curve expected in this experiment.
When the experimental measurements diverge at very low values of the voltages. When the ratio of current to saturated current is very small. That is, i/I less than or equal to 1/100. When there is a finite current at Voltage
V = 0
Diffusion will have influence on current - voltage curve in the working electrode which is ionization detector.
The estimation under set of conditions that is possible, despite the spherical shape of the working electrode, to use linear diffusion equations to theoretically predict the current vs voltage curve expected in this experiment will be:
When the experimental measurements diverge at very low values of the voltageswhen the ratio of current to saturated current is very small. That is, i/I less than or equal to 1/100When there is a finite current at Voltage V = 0Where
i = electric current
I = saturated current
V = voltage supplied
The curve expected will therefore give exponential curve from positive to negative domain because of the diffusion of ions from different directions
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A particular roller coaster has a mass of 3500 kg, a height of 4.0, and a velocity of 12m/s. What is the potential energy? If needed, use g=10.m/s^2
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
Gravitational Potential Energy of an object is calculated by formula ~
[tex] \large\boxed{\sf P = mgh}[/tex]
where,
m = mass of the object = 3500 kgg = Acceleration due to gravity = 12 m/s²h = height attained by the object = 4 mNow, let's calculate its potential energy ~
[tex]3500 \times 10 \times 4[/tex][tex]140000 \: \: joules[/tex][tex]140 \: \: kj[/tex]Answer:
Potential Energy of an object is calculated by formula:
Potential Energy (P.E)=m×g×hWhere,
m=mass of bodyg=acceleration due to gravityh=height from the earth surfaceNow, let's solve the question.
Given,
mass(m)=3500 kgheight (h)=4mvelocity (v)=10m/s²Now,
We know that,
Potential Energy (P.E)=mgh
[tex] = 3500 \times 10 \times 4[/tex]
[tex] = 3500 0\times 4[/tex]
[tex] =140000 joules [/tex]
[tex]\mathfrak{\blue{DisneyPrincess29}}[/tex]
how do i do this question in science?
simple subtract and ummmmmm.....
a block weighing (Fg) 500 N is resting on a steel table ( us=0.74) the minimum force start this block moving is?
The minimum force required to start this block moving is 370 N.
The given parameters;
weight of the block, W = 500 Ncoefficient of static friction, [tex]\mu_s[/tex] = 0.74The minimum force required to start this block moving is calculated as follows;
[tex]F= \mu_s F_n[/tex]
where;
[tex]F_n[/tex] is the normal force on the block which is equal to the weight of the block
[tex]F= \mu_s F_n \\\\F= \mu_s W\\\\F = 0.74 \times 500 \\\\F= 370 \ N[/tex]
Thus, the minimum force required to start this block moving is 370 N.
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how have astronomers interpreted the unexpectedly fast rotation of galaxies
Answer:
There must be a lot of dark matter that can be felt but not seen
The astronomers interpreted the unexpectedly fast rotation of galaxies that there must be a large quantity of dark energy whose gravity is detectable yet invisible.
What is a galaxy?Any system of stars plus interstellar material that makes up the cosmos is referred to as a galaxy. Such assemblages are common, and many of them are so massive that they hold tens of trillions of stars.
A vast variety of galaxies, from dim, hazy dwarf objects to spectacular spiral-shaped giants, have been created by nature. Almost all galaxies seem to have formed shortly after the universe started, and they are everywhere in space, even at the farthest limits of the universe that can be seen by the most advanced telescopes.
The majority of galaxies are found in clusters, many of which are further organized into clusters that span hundreds of billions of light-years.
Since there are almost empty spaces between these so-called super clusters, the universe's overall structure resembles a network of sheets or chains of galaxies.
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PLS HELP ASAP it's just 2 questions and they are multiple choice!
a bus increase its velocity from 30m/s to 45m/s and covers 300m distance. Find the time
Answer:
3.5 m/s²
Hope this helps, have a nice day/night! :D
which wave has a higher frequency and why?
Explanation:
the figure in the left side has higher frequency.
because it has more nos. of wave in 1sec.
can someone sent some gravity questions
Answer:
can gravity from waves
Explanation:
yes gravity can froms way
what is the molecular formula for the hydrocarbon in the mass spectrum above?
when light enters water, it bends. what does the amount of bending depend on?
Answer:
the change of speed!
Explanation:
if light speeds up or slow down more it bend more
A) infrared energy
B) microwave energy
C) radio wave energy
Answer:
Infrared energy
Explanation:
Answer:
A) infrared energy
Explanation: