Calculate the effort when a load of 72 N is raised using a block and tackle system of 5 pulleys
and efficiency 80%.
A. 11.52N
B. 18N
C. 57.6N
D. 288N

Answers

Answer 1
I would say it’s C but not sure

Related Questions

Where is the planet moving faster?

Answers

Do you mean what planets moves the fastest?

Allison pulls on a refrigerator with 200 N of force. Fred helps
her out and pulls on the refrigerator in the same direction with
300 N of force. What is the net force on the refrigerator?
N

Answers

Answer:500

Explanation:

If two forces are acting on an object in the same  direction, then they will add up and the net force will be the sum of their magnitudes. Thus, the net force on refrigerator is 500 N.

What is force?

Force is an external agent acting on a body to deform it or to change it form the state of rest or motion. There are various kinds of forces, such as gravitational force, frictional force, magnetic force etc.

If two forces are acting on a on an object in the same  direction, then they will add up and the net force will be the sum of their magnitudes. If they are acting from the opposite directions, they will cancel each other in magnitude and and the net force will be the subtracted value.

Here, both Allison and fred pulls the refrigerator from the same direction and the net force is the sum of  forces by each person. Therefore, the net force here is 300 + 200 = 500 N.

To find more on net force, refer here:

https://brainly.com/question/18031889

#SPJ2

which two things does force depend on?​

Answers

Answer:

Mass and Gravity

Explanation:

Objects with mass exert forces on each other via the force of gravity. This force is proportional to the mass of the two interacting objects and is inversely proportional to the square of the distance between them.

How are electromagnets similar to other magnets?

Answers

Answer:

Well, Both Are For Sure Magnets! But electromagnets need to use electricity!

Explanation:

A Wendys Roast For You!

A particle is moving with simple harmonic motion of period 8•0 s and amplitude 5•0 m Fine (A). The speed of the particle when it's 3•0 m from the centre of it's motion (B). The maximum speed (C). The maximum acceleration

Answers

Answer:

a. v(1.8) = -3.14 m/s

b. [tex]v_{max} = 3.925\ m/s[/tex]

c. [tex]a_{max} = 3.08\ m/s^2[/tex]

Explanation:

a.

The speed of a particle executing simple harmonic motion is given by the following equation:

[tex]v(t) = -A \omega \ Sin(\omega t)[/tex]

where,

v = velocity = ?

A = Amplitude = 5 m

ω = angular frequency = [tex]\frac{2\pi}{Time Period} = \frac{2\pi}{8\ s}[/tex] = 0.785 s

t = time

First we find time at 3 m by using equation for displacement:

[tex]x = 3\ m = ACos(\omega t)\\Cos((0.785 rad/s)(t)) = \frac{3\ m}{5\ m}\\t(0.785\ rad/s) = Cos^{-1} (0.6)\\t = \frac{0.927\ rad}{0.785\ rad/s}\\t = 1.18 s[/tex]

Therefore,

[tex]v(1.8) = velocity at 3\ m = -A\omega Sin(\omega t)\\v(1.8) = -(5\ m)(0.785\ rad/s)Sin((0.785\ rad/s)(1.18\ s))\\[/tex]

v(1.8) = -3.14 m/s

c.

The maximum speed is given as:

[tex]v_{max} = A\omega\\v_{max} = (5\ m)(0.785\ rad/s)\\[/tex]

[tex]v_{max} = 3.925\ m/s[/tex]

The maximum acceleration is given as:

[tex]a_{max} = A\omega^2\\v_{max} = (5\ m)(0.785\ rad/s)^2\\[/tex]

[tex]a_{max} = 3.08\ m/s^2[/tex]

HELP!
A position-time graph is shown below: (2 points)

Which statement accurately describes the speed of the object in the graph above over the four seconds?
O
Speed is increasing
Speed is constant.
Speed is decreasing.
Object is at rest.

Answers

Answer:

speed is increasing.

this is because the graph has a positive slope (due to it going up ), if it were decreasing, the graph would be going down

The speed of the object in the graph over the four seconds is increasing.

What is speed?

Speed is distance travelled by an object in unit time. A distance-time graph, also known as a distance-travel graph, is a graph that shows how an object's distance changes over time.A speed-time graph, often known as a speed curve, is a graph that shows how an object's speed changes over time.

Examining the speed-time and distance-time graphs for an entity that is at rest when time is zero and does not change speed will be our first step. The ensuing figure given in the question.

Given that in the question the graph has a positive slope as the line in graph is going up , if it were decreasing, the graph would be going down from this we conclude that speed of the object in the graph over the four seconds is increasing.

To learn more about speed refer to the link:

brainly.com/question/28224010

 #SPJ2

harold threw a baseball 3 meters harold is 2 meters tall. how fast did he throw the ball and how long was it in the air

Answers

Answer:

u = 7.74 m/s and t = 1.82 s

Explanation:

Given that,

Harold threw a baseball 3 meters.

Harold is 2 meters tall.

The vertical distance = 3m

The final velocity at the maximum height is  0.

Let u is the initial velocity of the baseball. Using the first equation of motion to find it as follows :

[tex]v^2-u^2=2as[/tex]

Here, a = -g

[tex]v^2-u^2=-2gs\\\\u=\sqrt{2gs} \\\\=\sqrt{2\times 10\times 3} \\\\=7.74\ m/s[/tex]

He has thrown it with the speed of 7.74 m/s

Let t is the time taken by the ball to fall on the ground.

Harold is 2 meters tall. Using second equation of motion to find it.

u = -7.74 (as downward direction is taken as positive)

[tex]s=ut+\dfrac{1}{2}at^2\\\\2=-7.74t+5t^2\\\\t=1.82\ s[/tex]

Hence, this is the required solution.

What are all stars made of

Answers

Stars are huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores. Aside from our sun, the dots of light we see in the sky are all light-years from Earth. They are the building blocks of galaxies, of which there are billions in the universe. It’s impossible to know how many stars exist, but astronomers estimate that in our Milky Way galaxy alone, there are about 300 billion.

When thermal energy is added to an object, what happens to the motion of the particles?

A.
increases

B.
decreases

C.
remains unchanged

D.
decreases, then increases

Answers

The answer is A

Explanation:

The snow fell on me is my excuse so my mom won’t know that I’m getting bullied

Answers

Answer:

Aaaaw noooo. :(

Explanation:

what did they say to u and what state do u live in. I will help u stand up to them. I have taken down many bullies before by using words. in fourth grade, my friend was getting bullied by the class, then yelled and stood up for her. they all fell silent and never bullied her, or any of my friends again. For whatever reason they bully u is probably d.u.m.b. which means they r really d.u.m.b. Also, U should try finding out a lot of personal info about them that they dont want anyone to know. also tell the principal. Is ur mom nice, or mean? if shes nice, she'll support u and fight for u, which means u should address

Answer:

You should stick up for yourself because if you don't then no one else will but im always here to talk to you if you need someone

Explanation:

Plz do all of it i will give brainlest and thanks to best answer
plz do it right

Answers

Answer:

C is the answer for the question

Answer:

reflection iim pretty sure

Explanation:

Instrument locations around Earth record seismic wave activity during an earthquake. The epicenter of the earthquake and locations of 4 instruments stations around Earth are shown. Which stations will record fewer waves than the others?

Answers

Answer:

explanations below

Explanation:

From the attached document, it can be seen that Stations 2 and 3 are further away from the epicenter unlike stations 1 and 4. Stations 2 and 3 are likely going to record fewer waves than the others because as the wave travel such distances, part of it are bent by the earth’s interior and some of the materials in earth also reflect some of the waves.

A fireboat is to fight fires at coastal areas by drawing seawater with a density of 1030 kg/m3 through a 10-cm-diameter pipe at a rate of 0.04 m3/s and discharging it through a hose nozzle with an exit diameter of 5 cm. The total irreversible head loss of the system is 3 m, and the position of the nozzle is 3 m above sea level. For a pump efficiency of 70 percent, determine the required shaft power input to the pump and the water discharge velocity.

Answers

Answer:

50.93 m/s

199.5 kW

Explanation:

From the question, the nozzle exit diameter = 5 cm, Radius= diameter/2= 5cm/2= 2.5cm. we can convert it to metre for unit consistency= (2.5×0.01)=

0.025m

We can calculate the The cross sectional area of the nozzle as

A= πr^2

A= π ×0.025^2

= 1.9635 ×10^- ³ m²

From the question, the water is moving through the pipe at a rate of 0.1 m /s , then for the water to move through it at a seconds, it must move at

(0.1 / 1.9635 ×10^- ³ m²)

= 50.93 m/s

During the Operation of the pump, the Dynamic energy of the water= potential energy provided there is no loss during the Operation

mgh = 1/2mv²

We can make "h" subject of the formula, which is the height of required head of water

h = (1/2mv²)/mg

h= v² / 2g

h = 50.93² / (2 ×9.81)

h = 132.21m

From the question;

The total irreversible head loss of the system = 3 m,

the given position of nozzle = 3 m

the total head the pump needed=(The total irreversible head loss of the system + the position of the nozzle + required head of water )

=(3 + 3 + 132.21m)

=138.21m

mass of water pumped in a seconds can be calculated since we know that mass is a product of volume and density

Volume= 0.1m³

Density of sea water=1030 kg/m

(0.1 m^3× 1030)

= 103kg

We can calculate the Potential enegry, which is = mgh

= (103 ×9.81 × 138.21)

= 139651.5 Watts

= 139.65kW

To determine required shaft power input to the pump and the water discharge velocity

Energy= efficiency × power

But we are given efficiency of 70 percent, then

139651.5 Watts = 0.7P

=199502.18 Watts

P=199.5 kW

Therefore, the required shaft power input to the pump and the water discharge velocity is 199.5 kW

BRAINLYIST ASAPPP write and claim evidence and reasoning statement that explains why mercury and Venus do not have any moons

Answers

answer:They are too close to the sun!

Explanation:Because Mercury is so close to the Sun and its gravity, it wouldn't be able to hold on to its own moon. Any moon would most likely crash into Mercury or maybe go into orbit around the Sun and eventually get pulled into it.Same with Venus!

Ram travel 50metre on a straight road in 30second . hari covers the same distance on the same road in 45s . who has done more work ? who has more ? Explain in short​

Answers

Answer:

The ram has done more work because the rate at which the ram work is 1.6m/s and Hari is 1.1m/s

Which scenario describes a transformation of thermal energy into chemical energy?
A You turn on the heater in your car.
B
The UV light from the Sun causes a sunburn.
С
The Sun's energy causes you to sweat.
D
The oven bakes dough into bread.

Answers

Answer:

The Answer is A

Explanation:

Which scenario describes a transformation of thermal energy into chemical energy? You turn on the heater in your car. The UV light from the Sun causes a sunburn. The Sun's energy causes you to sweat.

Why are states in the mid-central United States more likely to have tornados than other areas?

Answers

Answer:

because this is where Arctic air, cold fronts that have not been "weakened". As these fronts head further east, they sometimes lose their strength as they travel over more warm air.

A student wants to use a ramp to move boxes into a truck bed that is 3 m high. He has a choice of 2 different ramps. The length of one ramp is 4m, and the length of the other ramp is 6m. Which one will make his work easier?

Answers

Answer:

the ramp with 6 m length will be easier to work with.

Explanation:

the mechanical advantage of the ramp can be calculated to find out which ramp will be easier to work with. The ramp with greater mechanical advantage will be easier to work with. The formula for the mechanical advantage of ramp is given as follows:

[tex]M.A = \frac{L}{h} \\\\[/tex]

where,

M.A = Mechanical Advantage = ?

L = Length of Ramp

h = height of ramp = 3 m

FOR L =4 m:

[tex]M.A = \frac{4\ m}{3\ m}\\\\M.A = 1.33[/tex]

FOR L = 6 m:

[tex]M.A = \frac{6\ m}{3\ m}\\\\M.A = 2[/tex]

Since, the ramp with length 6 m has a greater mechanical advantage.

Therefore, the ramp with 6 m length will be easier to work with.

The second choice ramp with length of 6 m will make his work easier.

The given parameters;

height of the ramp, h = 3 mlength of the first ramp = 4 mlength of the second ramp = 6 m

The mechanical advantage of the each of the choices is calculated as follows;

First choice:

[tex]M.A = \frac{l_1}{h} \\\\M.A = \frac{4}{3} \\\\M.A = 1.333[/tex]

Second choice:

[tex]M.A = \frac{l_2}{h} \\\\M.A = \frac{6}{3} \\\\M.A = 2[/tex]

Thus, we can conclude that the second choice ramp with length of 6 m will make his work easier.

Learn more about mechanical advantage here:https://brainly.com/question/20487910

a roller coaster begins at the top of a hill if it acelerates at the rate of 2 m/s2 and has a mass of 2000 kg what net force is acting on it plzzz someone help im over here crying bc i dont know

Answers

Answer:

[tex]\boxed {\boxed {\sf 4000 \ Newtons }}[/tex]

Explanation:

Force can be found by multiplying the mass by the acceleration.

[tex]F=m*a[/tex]

The mass of the roller coaster is 2000 kilograms and the acceleration is 2 meters per second squared.

[tex]m= 2000 \ kg \\a= 2 \ m/s^2[/tex]

Substitute the values into the formula.

[tex]F= 2000 \ kg * 2 \ m/s^2[/tex]

Multiply.

[tex]F= 4000 \ kg*m/s^2[/tex]

1 kg*m/s² is equal to 1 NTherefore our answer of 4000 kg*m/s² is equal to 4000 Newtons

[tex]F= 4000 \ N[/tex]

The net force acting on the roller coaster is 4000 Newtons.

How do ions help your brain?

Answers

Generally speaking, negative ions increase the flow of oxygen to the brain resulting in higher alertness, decreased drowsiness, and more mental energy.
So, when talking about ions it’s very important to understand everything around..you consume everything you breathe in. It can effect you in many ways!!! Ok starting off, negative ions can help with more alert and stamina. These traits include longer and higher alertness, the decreasing of drowsiness when doing activities, and more mental energy!

A teacher needed to get a box of old books onto the top shelf of a bookcase in a new
apartment. The box was on the floor at the base of the bookcase. The box had a mass
of 15.0 kg, and it was lifted at a constant speed to the top shelf. A.220 B.22.5 C.0 D.16.5

Answers

Answer:

WHY THE HE!! DO YOU HAVE B00BS AS YOUR

PIC

Explanation:

A phase diagram assumes______
is kept constant.
Odensity
O volume
O temperature
O pressure

Answers

Choice D, pressure.
Pressure is the correct answer which is D

Electromagnetic waves are sometimes demonstrated by rippling waves in water. However, electromagnetic waves are different from water waves. Which is a
characteristic that makes electromagnetic waves and water waves different?
O A. All water waves have higher frequencies.
OB. All water waves have longer wavelengths.
OC. All electromagnetic waves are transverse waves.
O D. All electromagnetic waves can travel in a vacuum.

Answers

The answer is D: all electromagnetic waves can travel in a vacuum
D my teacher had gone over it with us before

Formulas
Speed = distance / time
Time = distance / speed
Distance = speed x time
A bowling ball rolls 30 meters in 4 seconds. What speed did it travel?
distance = 30m
time = 45
speed = ?

Answers

Using s= d/t

7.5 m per second

Speed = distance/time
= 30/45
= 6/9
= 2/3
= 0.666.........
Speed = 0.6

Plz do all of it i will give brainlest and thanks to best answer
plz do it right

Answers

Answer:

d

Explanation:

Answer:

Earth absorbs heat from the sun.

Explanation:

This radiation is absorbed by greenhouse gases which then radiate energy into all directions including downwards and thereby trapping heat in the atmosphere.

Hope you have a good day :)

If a machine is doing 500 J of work with 75 watts of power, how long did it take to complete its task?
SHOW WORK!!!!!!

Answers

Answer:

time = 6.67secs

Explanation:

power = workdone( energy) / time

therefore :

Time = workdone / power

time = 500 / 75

time = 6.67secs

Based on Newton's law of action-reaction, which arrow represents the force that the seat belt would exert on the man's body if he had to slam on the brakes?

Answers

Answer:

c. Y

Explanation:

Newton's third law of motion states that action and reaction are equal and opposite. Hence for every action, there is an equal and opposite reaction.

Considering the system of forces shown in the image, W and Y are  opposite forces. When the driver slams on the brakes, he will be pushed forward towards the windscreen. The force Y exerted by the seat belt keeps him on the drivers seat by moving him backwards towards the seat.

plzzzz help it for civics

Answers

Answer:

A : the colonists dumped tea in Boston Harbor

A 2 kg blue car is moving 6 m/s to the right and collides with a 3 kg red car that is moving 2 m/s to the left. The cars collide and stick together. What is their velocity after the collision? Include units on your answer.

Answers

Answer:

Their velocity after the collision is 1.2 m/s, to the right.

Explanation:

Given;

mass of the blue car, m₁ = 2 kg

initial velocity of the blue car, u₁ = 6 m/s

mass of the red car, m₂ = 3 kg

initial velocity of the red car, u₂ = 2 m/s

let the blue car moving to the right be in positive direction

also, let the red car moving to the left be in negative direction

Apply the principle of conservation of linear momentum for inelastic collision.

m₁u₁ - m₂u₂ = v(m₁ + m₂)

where;

v is their velocity after the collision

(2 x 6) - (3 x 2) = v(2 + 3)

12 - 6 = 5v

6 = 5v

v = 6/5

v = 1.2 m/s, to the right

Therefore, their velocity after the collision is 1.2 m/s, to the right.

What do you think menas to be Physically fit.

Answers

Answer:

consistently working out and eating healthy i guess

Explanation:

Answer:

To have a strong body (not only visible muscles). Physically fit is to eat well also. Eat healthy more! Your body might not be packin, but it sure is strong!

Explanation:

Hope this Helps!

Have a great day!

:)

Other Questions
Please helpppp! Will give Brainliest!(wizard of oz)What major life experiences have played a significant role in Dorothy's personality? List two events and give examples from the story, explaining how each event shaped the character. Why are metals good conductors of heat?O A. The free-moving electrons transmit heat quickly.B. The malleable atoms slide past each other, transmitting heat.O c. The formation of alloys allows a path for heat to travel.O D. The ductility allows heat to move along an edge quickly. What is the range in interval notation? The earths gravity is pulling on you. Are you pulling on the earth? Explain your reasoning. Help with mathh pleaseeee help it is easy just read an =d answer please This area also receives rain during the monsoon season. While many people associate this season as a time of intense rain it is actually a time when the winds change. During Indias monsoon season, hot air flows across the Indian Ocean and forms clouds full of water. As these clouds move across the cooler land it drops its rain, often resulting in floods. What does the word monsoon mean in the text? Annual wet weather pattern Strong storm Heavy rain Flooding What is the value of A if sin (A) = 32?Not here604530 The main difference between the four nucleotides that make up DNA is that they have differentsugars.uracil.bonds.bases. Will mark brainliest Please select the word from the list that best fits the definitionSponsors,pilgrimageshahtolerancenomadsFive Pillars of IslamminaretBaburjihadmosquecaravanpatronscaliphcalligraphy How did the Union plan to defeat the Confederacy? Check all that apply.fighting major sea battles between 1861 and 1862taking control of the Mississippi Rivermaking early plans of the Confederacy to protect Southern portscreating a blockade of Confederate portsdividing the Confederacy to weaken it List three things to be safer online. need help math question 24. Extra Credit: A Yule Log is traditionally made of...cakeO fhearswoodO candy what is the percent increase from 37.7 to 75.4 Where is your uncle? He.. to market. He 'll be back soon. (go) A 2150 kg car, moving east at 10.0 m/s, collides and joins with a 3250 kg car. The cars move east together at 5.22 m/s. What is the 3250 kg cars initial velocity calculated to the nearest tenth? Record your answer in the boxes below. Be sure to use the correct place value. what is a nuclear energy? PLEASE HURRY!!Which two mountain regions have fertile land suitable for farming?A. Appalachian Plateau and PiedmontB. Blue Ridge and Ridge and ValleyC. Piedmont and Blue RidgeD. Appalachian Plateau and Ridge and Valley Harold and his friend Bill each collect vintage action figures. Harold already has18 action figures and adds 3 more figures to his collection each month. Billalready has 24 action figures and adds 2 more to his collection each month. Let xrepresent the number of months, and y represent the number of action figures.Which equations can be used to find how long it will take before the friends eachhave the same number of action figures? Evaluate the expression for the given value of the variable.2x +9 for x = 14The expression equals