1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
LUCKY_DIMON [66]
3 years ago
14

Two workers are sliding 470 kg crate across the floor. One worker pushes forward on the crate with a force of 450 N while the ot

her pulls in the same direction with a force of 330 N using a rope connected to the crate. Both forces are horizontal, and the crate slides with a constant speed. What is the crate's coefficient of kinetic friction on the floor?
Physics
1 answer:
nydimaria [60]3 years ago
8 0

Answer:

0.169

Explanation:

There are three forces acting on the crate along the horizontal direction:

- The pushing force of the first worker, F1 = 450 N forward

- The pushing force of the second worker, F2 = 330 N forward

- The frictional force F_f acting backward

The crate slides with constant speed, so its acceleration is zero: a = 0. This means that we can write Newton's second law as

\sum F = ma = 0\\F_1 + F_2 - F_f = 0

The frictional force can be rewritten as

F_f = \mu mg

where

\mu is the coefficient of kinetic friction

m = 470 kg is the mass of the crate

g = 9.8 m/s^2 is the acceleration due to gravity

Substituting everything into the previous equation, we find:

F_1 + F_2 - \mu mg = 0\\\mu = \frac{F_1 + F_2}{mg}=\frac{450 N+330 N}{(470 kg)(9.8 m/s^2)}=0.169

You might be interested in
In 1990, Dave Campos of the United States rode a special motorcycle called the Easyrider at an average speed of 518 km/h. Suppos
maks197457 [2]

The distance travelled during the given time can be found out by using the equations of motion.

The distance traveled during the time interval is "13810.8 m".

First, we will find the deceleration of the motorcycle by using the first <em>equation of motion</em>:

v_f=v_it+at\\\\

where,

vi = initial velocity = (518 km/h)(\frac{1\ h}{3600\ s})(\frac{1000\ m}{1\ km}) = 143.89 m/s

vf = final veocity = 60 % of 143.89 m/s = (0.6)(143.89 m/s) = 86.33 m/s

a = deceleration = ?

t =time interval = 2 min = 120 s

Therefore,

86.33\ m/s = 143.89\ m/s + a(120\ s)\\\\a = \frac{86.33\ m/s - 143.89\ m/s}{120\ s}

a = -0.48 m/s²

Now, we will use the second <em>equation of motion </em>to find out the distance traveled (s):

s = v_it+\frac{1}{2}at^2\\\\s = (143.89\ m/s)(120\ s)+\frac{1}{2}(-0.48\ m/s^2)(120\ s)^2\\\\s = 17266.8\ m - 3456\ m

<u>s = 13810.8 m = 13.81 km</u>

<u />

Learn more about the equations of motion here:

brainly.com/question/20594939?referrer=searchResults

The attached picture shows the equations of motion.

6 0
3 years ago
Paula has walked in a straight line, 30.5° north of west, for 1650 meters. How far south and east should she walks to return to
olchik [2.2K]
The answer is A.
Sy = 1650 x sin30.5 = 837.4 m toward south
Sx = 1650 x cos30.5 = 1421.7 m toward east
8 0
2 years ago
The lift does 3000 J of work in 5 seconds. What is the power of the lift?
diamong [38]

Answer:

600

Explanation:

p=Work/time

3000/5=600 is power

8 0
3 years ago
Why does the mass spectrum of Br2 contain three signals whose heights are almost in the ratio of 1:2:1? What are the origins of
Eddi Din [679]
<span>The element bromine has two isotopes: Br-79 and Br-81, with a 50%-50% isotopic abundance. Statistically, 25% of bromine molecules will be Br79-Br79, 25% will be Br81-Br81 and 50% will be Br79-Br81. This is equivalent to a ratio of 1:1:2 or 1:2:1. The peaks in a mass spectrum just like chromatography reflect this relative abundance of different isotopic combinations.</span>
3 0
3 years ago
The atom in the diagram has a neutral charge how many protons does it have
Olegator [25]

Explanation:

This should be of help:

An atom is made up of three subatomic particles:

  • Protons are the positively charged particles.
  • Electrons are the negatively charged particles.
  • Neutrons do not carry any charges.

A neutral atom is an atom that has not lost or gained any amount of electrons.

In a neutral atom;

                the number of protons and electrons are the same

 Usually atoms are designated this way:

                                                  ᵃₙX

  where X is the symbol of the atom

               a is the mass number of the atom

                n is the atomic number of the atom

 The mass number = number of protons + number of neutrons

        Atomic number = number of protons

Note; atomic number is the same as the number protons and the number of electrons in a neutral atom.

Use this guide to solve the problem

Learn more:

Atomic number brainly.com/question/5425825

#learnwithBrainly

8 0
3 years ago
Other questions:
  • PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!
    7·1 answer
  • A singly ionized helium atom is in the ground state. It absorbs energy and makes a transition to the n = 3 excited state. The io
    8·1 answer
  • Explain How people can achieve an environmentally sustainable society .
    7·1 answer
  • What are five ways to decrease resistance?
    11·1 answer
  • Help mee (:
    8·1 answer
  • Why do you need to breath faster at the top of a mountain
    15·1 answer
  • A flat coil of wire is placed in a uniform magnetic field that is in the y-direction.
    11·1 answer
  • Scenario 2: A dam was built California in 1999 to block the Santa Ana River and help generate
    10·1 answer
  • What power does a toaster with 15 A of current and 20 Ωof resistance consume?
    10·2 answers
  • A wave raises a buoy twice every second and the crests of the incoming waves are 4m apart
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!