a machine
of efficiency of 70% is used to raise
a body of
mass 80 kg through
a vertical distance of 3m in
40 seconds. Calculate the power input. (Take g = 10 m/s²)​

Answers

Answer 1

Answer:

Power_input = 85.71 [W]

Explanation:

To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.

 [tex]W =F*d[/tex]

where:

W = work [J] (units of Joules)

F = force [N] (units of Newton)

d = distance [m]

We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.

Now replacing:

 [tex]W=m*g*d[/tex]

[tex]W=80*10*3\\W=2400[J][/tex]

Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.

 [tex]P=W/t[/tex]

where:

P = power [W] (units of watts)

W = work [J]

t = time = 40 [s]

[tex]P=W/t\\P=2400/40\\P=60 [W][/tex]

The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.

 [tex]Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}= 60/0.7\\P_{introduced}=85.71[W][/tex]


Related Questions

the maximum intensity levels of a trumpet, trombone, and a bass drum, each at a distance of 3m are 94 dB, 107dB, and 113dB respectively. What is the intensity level of the three different instruments when played simultaneously, again at 3m?

Answers

Answer:

β = 114 db

Explanation:

The intensity of sound in decibles is

          β = 10 log [tex]\frac{I}{I_{o}}[/tex]

in most cases Io is the hearing threshold 1 10-12 W / cm²

let's calculate the intensity of each instrument

            I / I₀ = 10 (β / 10)

            I = I₀ 10 (β / 10)

trumpet

            I1 = 1 10⁻¹² 10 (94/10)

            I1 = 2.51 10⁻³ / cm²

Thrombus

           I2 = 1 10⁻¹² 10 (107/10)

           I2 = 5.01 10-2 W / cm²

low

           I3 =1 1-12    (113/10) W/cm²

            I3 = 1,995 10-1 W / cm²

when we place the three instruments together their sounds reinforce

           I_total = I₁ + I₂ + I₃

           I_ttoal = 2.51 10-3 + 5.01 10-2 + ​​1.995 10-1

           I_total = 0.00251 + 0.0501 + 0.1995

           I_total = 0.25211 W / cm²

let's bring this amount to the SI system

         β = 10 log (0.25211 / 1 10⁻¹²)

           β = 114 db

What is food called when it enters the pharynx?

A.Bile
B.bolus
C. Food
D. Feces

Answers

Answer:

its food this was easy

The diagram shows an electromagnet made with copper wire, a steel nail,
and a 1.5 V battery. Which change would make this electromagnet weaker?

A. Reverse the direction of the battery

B. Rap more coils around the nail

C. Replace the steel nail with a wooden stick

D. Replace the battery with a 3V battery

Correct answer is C

Answers

If an electromagnet is made with copper wire, a steel nail, and a 1.5 V battery then replacing the steel nail with a wooden stick would make this electromagnet weaker, therefore the correct answer is option C.

What is electromagnetic force?

It is a type of force that occur between electrically charged particles. The electromagnetic force is the combination of all the electrical and magnetic forces generated by any charged particle.

As given in the problem statement diagram shows an electromagnet made with copper wire, a steel nail, and a 1.5 V battery, then we have to find out which change would make this electromagnet weaker,

Hence, By replacing the steel nail with a wooden stick would make this electromagnet weaker, therefore the correct answer is option C.

To learn more about electromagnetic forces, refer to the link;

brainly.com/question/13191643

#SPJ5

A solid disk rotates in the horizontal plane at an angular velocity of 0.649 rpm with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.101 kg m2. From above, sand is dropped straight down onto this rotating disk, so that a thin uniform ring of sand is formed at a distance of 0.415 m from the axis. The sand in the ring has a mass of 0.499 kg. After all the sand is in place, what is the angular velocity of the disk

Answers

Answer:

The angular velocity of the disk is 0.0369 rad/sec.

Explanation:

Convert 0.649 rpm to rad/s

0.649 rpm = 0.649 * (2π/60) = 0.0679rad/sec

From the question,

Summation of final angular momentum equals summation of initial angular momentum

I*w = Io*wo

w = wo (lo/I)

But I = Isand + Io

and Isand = Msand * R²sand

Therefore, w = wo (lo/I) = wo (Io/Msand * R²sand + Io)

Where,

wo = 0.0679rad/sec

Io = 0.101 kg m2

Msand = 0.499 kg

Rsand = 0.415 m

Hence,

w = 0.0679 {0.101/(0.499*(0.415)²+0.101)}

w = 0.0679 (0.101/0.1869)

w = 0.0679*0.544 = 0.0369 rad/sec

The angular velocity of the disk is 0.0369 rad/sec.

In specific heat capacity experiment, the ammeter in circuit is connected in

Answers

Answer:

In series

Explanation:

In such experiment, the ammeter is connected in series with the heater, in order to measure the circulating current.

By the way, ammeters are always connected in series in circuits to measure the running current in it.

Obesity and stress are confirmed risk factors for which of the following?

Answers

lost of nutrition in human

Answer:

True

Explanation:

Obesity and stress are confirmed risk factors for CHD

A Ferris wheel with 60 spokes has a diameter of 100 m. It makes one rotation every 60 seconds. Find the speed of the passengers when the Ferris wheel is rotating at this rate.

Answers

Answer:

The speed of the passengers is 5.24 m/s

Explanation:

Uniform Circular Motion

It occurs when an object in a circular path travels equal angles in equal times.

The angular speed can be calculated in two different ways:

[tex]\displaystyle \omega=\frac{v}{r}[/tex]

Where:

v = tangential speed

r = radius of the circle described by the rotating object

Also:

[tex]\omega=2\pi f[/tex]

Where:

f = frequency

Since the frequency is calculated when the number of revolutions n and the time t are known:

[tex]\displaystyle f=\frac{n}{t}[/tex]

The Ferris wheel has a diameter of 100 m and makes n=1 rotation in t=60 seconds, thus the frequency is:

[tex]\displaystyle f=\frac{1}{60}\ Hz[/tex]

The angular speed is:

[tex]\displaystyle \omega=2\pi \frac{1}{60} =\frac{\pi}{30} \ rad/s[/tex]

Now we calculate the tangential speed, solving this formula for v:

[tex]\displaystyle \omega=\frac{v}{r}[/tex]

[tex]v=\omega . r[/tex]

The radius is half the diameter, r=100/2=50 m:

[tex]\displaystyle v=\frac{\pi}{30} . 50[/tex]

Calculating:

v = 5.24 m/s

The speed of the passengers is 5.24 m/s

3. A cart (m= 10.0 kg) is currently traveling with a velocity of 3.0 m/s. The cart then gains speed,
achieving a new velocity of 7.0 m/s after 8.0 seconds. Calculate the magnitude of the net force acting
on the cart.
A 0.0 N
B. 1.25 N
C. 5.0 N
D. 80N

Answers

First we calculate the acceleration of the cart:

a = (v₂ - v₁) / (t)

a = (7 m/s - 3 m/s) / (8 s)

a = 4 m/s / 8 s

a = 0.5 m/s²

Using the Newtons Second Law:

F = m×a

F = (10 kg)(0.5 m/s²)

F = 5 N

The correct option is C

a boy pushing a 200kg object on the floor it begins from rest and reaches 20 m/s² in 10 minutes, what is it's acceleration?​

Answers

Answer:

I hope the above pic helps you mate

I will always help you understanding your assingments

have a great day

#Captainpower:)

What makes metal a good conductor?

Answers

Answer:

It is one of the strongest materials in the world and can hold anything

An object at rest is suddenly broken apart into two fragments by an explosion. The first fragment (with mass m1) acquires twice the kinetic energy of the second one (with mass m2).
What is the ratio of their masses?

Answers

Answer:

m1 ÷ m2 = 1 ÷ 2

Explanation:

The ratio of their masses is as follows:

As it is given that the mass m1 is twice of mass m2

So the equation could be written as

[tex]\frac{1}{2} m1 v1 v1 = 2 \times \frac{1}{2} m2 v2 v2\\\\\frac{m1}{m2} = \frac{2 v2 v2}{v1 v1} ..........(1)[/tex]

Here we used the  conservation of momentum

Prior to the explosion, the object is in rest so the momentum would be zero but after the explosion the total momentum would be  m1v1 + m2v2,  that is also zero.

So,

[tex]m1 v1 + m2 v2 = 0\\\\m1 v1 = - m2 v2\\\\\frac{m1}{m2} = \frac{- v2}{v1}[/tex]

Now squaring to the both sides

m1 m1 ÷ (m2 m2) = v2 v2 ÷ (v1 v1) ........(2 )

Solved both the equations

After solving it, the ratio is

m1 ÷ m2 = 1 ÷ 2


The weight of the bricks is 5000N. Calculate the mass of the bricks.
(1 kg weighs 10N)

Answers

Answer:

500kg

Explanation:

....................

Answer:

500Kg

Explanation:

1 kg = 10N

? =5000N

5000N÷10N * 1Kg = 500Kg

A block with a mass of 0.30 kg is attached to a horizontal spring. The block is pulled back from its equilibrium position until the spring exerts a force of 1.2 N on the block. When the block is released, it oscillates with a frequency of 1.1 Hz.
How far was the block pulled back before being released?

Answers

Answer:

The value is  [tex]x = 0.084 \ m[/tex]

Explanation:

From the question we are told that

   The mass of the block is  [tex]m = 0.30 \ kg[/tex]

   The force exerted is  [tex]F = 1.2 \ N[/tex]

   The  frequency is  [tex]f = 1.1 \ Hz[/tex]

Generally the spring constant of the spring is mathematically represented as

       [tex]k = (2 \pi f)^2 * m[/tex]

=>    [tex]k = (2 * 3.142 * 1.1 )^2 * 0.30[/tex]

=>    [tex]k = 14.33 \ N/m[/tex]

Generally the spring constant is also mathematically represented as

      [tex]k = \frac{ F }{x }[/tex]

=>   [tex]14.33 = \frac{ 1.2 }{x }[/tex]

=>   [tex]x = 0.084 \ m[/tex]

What is the slope of the line that passes through the points (-8, -3)(−8,−3) and (-12, -3) ?(−12,−3)? Write your answer in the simplest form.
single black dude

Answers

Notice that both of those points are 3 units below the x-axis. So the line is horizontal ... its slope is zero.

Which of the following cars have the most kinetic energy

Answers

Hey There!_____________________________________Answer:

[tex]\huge\boxed{OptionA}[/tex]

_____________________________________DATA:Blue Car:

mass = 4 kg

velocity = 5 m/s^2

Orange truck:

Mass= 2kg

Velocity = 7m/s^2

Grey Car:

mass = 6 kg

velocity = 4m/s^2

Green Car:

Mass = 8 kg

Velocity = 3 m/s^2

_____________________________________SOLUTION:

By the equation of kinetic energy,

                                       

                                         K.E = [tex]\frac{1}{2} mv^2[/tex]

Where,

            K.E is kinetic energy

            m is mass

            v is velocity

_____________________________________Kinetic energy of Blue car:

 

Directly substitute the variables in the equation,

                                       

                                       K.E = [tex]\frac{1}{2}x4x5^2[/tex]

Simplify the equation,

                                       K.E = 50 J

_____________________________________Kinetic Energy of Silver Car:

                                           

 Directly substitude the variable in the equation,

                                                           

                                        K.E = [tex]\frac{1}{2}x6x4^2[/tex]

Simplify the equation,

                                        K.E = 48J

_____________________________________Kinetic Energy of Green Car:

Substitute the variables in the equation,

                                         

                                         K.E = [tex]\frac{1}{2}x8x3^2[/tex]

Simplify the Equation,

                                         

                                         K.E = 36J

_____________________________________Kinetic Energy of Orange Truck:

Substitute the variable,

                                        K.E = [tex]\frac{1}{2}x 2x7^2[/tex]

Simplify the equation,

                                     

                                        K.E = 49J

_____________________________________

As you can see that the highest value of kinetic energy is of Blue SUV thus it will be out answer.

_____________________________________Best Regards,'Borz'

Where are you atera11

Answers

Answer:

? who is atera11?

Explanation:

A car moving initially at 20 m/s accelerates up to 60 m/s during the
course of 5 seconds. The average acceleration of the car is m/s2

Answers

Gain in velocity = 60 - 30 = 30 m/s.

Time taken for this gain = 5 seconds

Average acceleration = 30 / 5 = 6 m/s/s.

So, 6 metres per second squared.
472 viewsView 2 Upvoters
Related Questions (More Answers Below)

ASAP DUE TO DAY PLS HELP MEEEEEE

1. Kinetic energy is the energy of:
A. potential
B. objects at rest
C. objects in motion
D. accelerating objects
--------------------------------------------------------------------------------------------

Answers

i believe it is c, objects in motion. i apologize i’m im wrong.

You have to move your 100 N couch before a delivery company drops off your new one. Unfortunately your roommate is passed out on it. The coefficient of friction between the couch and floor is .43. It takes 250 N of force to get the couch moving. a) How much does your roommate weigh in Newton’s? b) After you get the couch moving it only takes 200 N to keep it moving at a constant speed, what is the coefficient of kinetic friction?

Answers

Answer:

a) Weight of Roommate = 481.4 N

b) μk = 0.34

Explanation:

a)

The force required to move the couch must be equal to the force of friction:

F = frictional force

F = μW

W = F/μ

where,

W = Total Weight of Couch and Roommate

F = Force Required start to move couch = 250 N

μ = coefficient of static friction between couch and floor = 0.43

Therefore,

[tex]W = \frac{250 N}{0.43}\\\\W = 581.4 N[/tex]

So, the total weight is given as:

W = Weight of Couch + Weight of Roommate

Weight of Roommate = W - Weight of Couch

Weight of Roommate = 581.4 N - 100 N

Weight of Roommate = 481.4 N

b)

Now, the force required to keep the couch moving can be given as equal to the kinetic friction force:

F = kinetic friction

F = μk*W

μk = F/W

where,

μk = coefficient of kinetic friction = ?

F = Force required to keep the couch moving = 200 N

Therefore,

μk = 200 N/581.4 N

μk = 0.34

ASAP
What is elastic potential energy?

Answers

Answer:

Elastic potential energy is stored when materials stretch or compress. Examples of it include springs, rubber bands, and slingshots.

Explanation:

If you add a light bulb to the circuit, the filament in the bulb will resist the flow of
electrons and convert energy into____and_____

a.)light and heat
b.)electrons and neutrons
c.)energy and matter
d.)electrons and protons

Answers

Answer:

Light and heat!

Explanation:

This is correct<3

Answer:

light and heat

Explanation:

i love science

HELP ASAP!! i’ll mark you the brainliest!!

Answers

Answer:

yes

Explanation:

Ultimate frisbee relies upon good sportsmanship since there are no referees and players must self-officiate the game. What is this known as?
Group of answer choices

Spirit of the Team

Spirit of the Frisbee

Spirit of Sportsmanship

Spirit of the Game

Answers

Answer:

spirit of the team / game

What speed should a satellite with a mass of 1500 kg at 8,500 km above the center of the earth be traveling at in order to stay in orbit (remember the mass of the earth is 5.97×10 to the 24th kg ) (in m/s , G= 6.67×10 to the -11 n (m/kg) ^2)

Answers

Answer:

6844.5 m/s.

Explanation:

To get the speed of the satellite, the centripetal force on it must be enough to change its direction. This therefore means that the centripetal force must be equal to the gravitational force.

Formula for centripetal force is;

F_c = mv²/r

Formula for gravitational force is:

F_g = GmM/r²

Thus;

mv²/r = GmM/r²

m is the mass of the satellite and M is mass of the earth.

Making v the subject, we have;

v = √(GM/r)

We are given;

G = 6.67 × 10^(-11) m/kg²

M = 5.97 × 10^(24) kg

r = 8500 km = 8500000

Thus;

v = √((6.67 × 10^(-11) × (5.97 × 10^(24)) /8500000) = 6844.5 m/s.

Answer:

6.8 × 10³ m/s

Explanation:

for those using CK12, the answer, (6.78 × 10³ m/s), rounds to 6.8 × 10³ m/s

Which of the following is true of changes in momentum?

A small force may produce a large change in momentum by acting over a short time interval.

A large force may produce a small change in momentum by acting over a short time interval.

A small force may produce a large change in momentum by acting on a very massive object.

A small force may produce a large change in momentum by acting over a short distance.

can you please explain why this is the answer as well and how you got it?

Answers

Answer: ⇒  Answer is 3

Explanation: momentum = mass × velocity

"A small force may produce a large change in momentum by acting on a very massive object".

THEY HAVEN'T GIVEN US THE TIME PERIOD NOR THE DISTANCE TRAVELED. THEREFORE WE CANNOT ACTUALLY DECIDE IF THE FORCE IS KEPT FOR A LONG TIME OR SHORT TIME. ANYWAYS SINCE THE MASS IS GIVEN AS MASSIVE , THE  MOMENTUM SHOULD BE DEFINITELY HIGH.

WHY I SAY OTHERS ARE WRONG:

1) For a small force to give a large change in momentum, it should act for a long time interval.

2) By applying a large force for a short time interval, the change of momentum should be large.

3) Correct answer.

4) Acting over a short distance can be the same as acting over a short period of time.Therefore the distance should be large in order for a larger momentum.

I HOPE IT HELPS!

The true statement is required.

The true statement is A large force the change in momentum may be small acting over a short time interval.

Force is given by

[tex]F=ma[/tex]

m = Mass of object

a = Acceleration = [tex]\dfrac{v-u}{t}[/tex]

t = Time

So, force is

[tex]F=m\dfrac{v-u}{t}\\\Rightarrow F=\dfrac{mv-mu}{t}\\\Rightarrow F=\dfrac{\Delta p}{t}[/tex]

[tex]\Delta p[/tex] = Change in momentum.

If the time taken is small then the force will be large.

The change in momentum can also be small.

So, for a large force the change in momentum may be small acting over a short time interval.

Learn more:

https://brainly.com/question/14559060

https://brainly.com/question/18762737

As a woman walks, her entire weight is momentarily placed on one heel of her high-heeled shoes. Calculate the pressure exerted on the floor by the heel if it has an area of 1.60 cm2 and the woman's mass is 54.0 kg. Express the force in N/m2 and lb/in2. (In the early days of commercial flight, women were not allowed to wear high-heeled shoes because aircraft floors were too thin to resist such large pressures.)

Answers

Answer:

P = 3.3075 x 10⁶ N/m² = 479.71 lb/in²

Explanation:

In order to find the pressure , we first need to find the force exerted by the lady. The force must be equal to the weight of the lady:

Force = F = Weight = mg

F = mg = (54 kg)(9.8 m/s²)

F = 529.2 N

Now, we convert area to S.I unit:

Area = A = (1.6 cm²)(1 m/100 cm)²

A = 1.6 x 10⁻⁴ m²

Now, the pressure can be calculated as:

Pressure = P = F/A

P = 529.2 N/1.6 x 10⁻⁴ m²

P = 3.3075 x 10⁶ N/m²

Now, we convert this into lb/in²:

P = (3.3075 x 10⁶ N/m²)[(0.000145038 lb/in²)/(1 N/m²)

P = 479.71 lb/in²

a book falls off a 1-meter tall table. how long will it take for the book to hit the floor ?

Answers

Answer:

0.45 s

Explanation:

Step 1: Given and required data

Displacement of the book (s): 1 mInitial velocity of the book (u): 0 m/s (rest)Acceleration due to the gravitational force of Earth (a): 9.8 m/s²

Step 2: Calculate the time that it will take for the book to hit the floor (t)

The book undergoes a Uniformly Accelerated Motion. We can calculate the time required to reach the floor using the following suvat equation.

s = u × t + 1/2 × a × t²

s = 0 m/s × t + 1/2 × a × t²

s = 1/2 × a × t²

t = √(2s/a)

t = √(2 × 1 m/9.8 m/s²)

t = 0.45 s

Which term best describes the motion of the rope particles in relation to the motion of the rope wave shown in the photograph

Answers

Answer:

A: Perpendicular

Explanation:

The question is incomplete as it lacks the image of the rope wave motion.

However, as found on "estudyassistant", the options are;

A) Perpendicular

B) Circular

C) Longitudinal

D) Parallel

From all that, we can say that;

The rope's are moving simultaneously in the same pattern without touching each other.

This is therefore a mechanical wave being created with the motion having oscillations that are perpendicular to the direction of energy transfer of the ropes.

This is a definition of transverse waves because the rope particle motion is perpendicular to the wave motion.

Answer:

A: Perpendicular

Explanation:

Read above explanation.

2/3


If the crate has a mass of 80 kg, how much would it weigh?

Answers

are you asking if what it would weigh in lbs?

you are driving at 18m/s down Lyndale​ avenue. A car backs out a driveway 25 meters in front of you. You continue at that speed while your brain processes the danger which takes 0.25 seconds. You then slam on the brakes and your car has an acceleration of -5.4m/s^2. Do you stop before reaching the driveway(and hitting the car)? Show your work. This is a two-part​ problem with constant speed and braking.

Answers

Hello!

For this, first let's calculate time of stop:

t = (V - Vi) / a

Replacing:

t = (0 m/s - 18 m/s) / -5,4 m/s^2

Resolving:

t = -18 m/s / -5,4 m/s^2

t = 3,33 s + 0,25 s = 3,58 s

Now lets calculate distance traveled, with formula:

d = Vi*t + (a*t^2)/2

Replacing:

d = 18 m/s * 3,58 s + (-5,4 m/s^2 * (3,58 s)^2) /2

Resolving:

d = 64,44 m + (-34,604 m)

d = 29,83 m

Then, the vehicle will CRASH

Other Questions
Where were silk-producing cocoons found in China .What was a result of King Philips War for the regions Native Americans?A.They received a large land grant.B.They signed a treaty giving up their land.C.They lost their power in New England.D.They were able to slow down colonial settlement. Vengas a la tienda. Correct Incorrect What are the 4 ways structural adaptations affect a plant or an animal? Bruces hourly wage increased from $15.00 to $18.60. What percent of change does this represent? What is 37777 using index notation How is acids and bases connected to Physical Science? Could u give me brief summary of New Years 75 POINTS!!!!! Would someone write an essay that consists of 500 words or more on the Seven Deadly Sins? It has to be translated to Spanish so you'll have to use basic words, nothing constructive please. Thank you! Its due by 8 in the morning.. You are standing on a moving bus, facing forward, and you suddenly fall forward. You can imply form this that the buss Select the correct answer.The words courageous and gracious share the same suffix, -ous. What is the correct meaning of this suffix?A. ableB. withoutC. full ofD. too littleE. again the surface "s" area of a sphere of radius " r" is given by the formula of s= 4r^2find;1, the surface area of a sphere whose radius is 5 cm 2,the radius of a sphere whose surface area is 23716/81 How can this sentence be rewritten to use an adverb of frequency?Teresa prepara la comida los lunes, los martes, los mircoles, los jueves, los viernes, los sbados, y los domingos. 1. Teresa prepara la comida rara vez.2. Teresa prepara la comida todos los das.3. Teresa prepara la comida poco.4. Teresa prepara la comida de vez en cuando. One of the functions of an IDE is to check for: flowchart errors. Syntax errors. memory errors X input and output. theThe shape of a garden is rectangular in the middle and semi circularat the ends as shown in the diagram. Find the area and the perimeter.of this garden [Length of rectangle is7m 20-(3.5 +3.59 metres).1DI20 m please give me drawing tips Which way can heat never flow? defined as a condition in which an individaul has enough energy to avoid fatigue and enjoy life help pls:) :) :) :) :) :) :) :) :) bro imagine getting chased by the cops in a mini van