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
katovenus [111]
3 years ago
10

A crate of 45.2-kg tools rests on a horizontal floor. You exert a gradually increasing horizontal push on it and observe that th

e crate just begins to move when your force exceeds 321 N . After that you must reduce your push to 205 N to keep it moving at a steady 22.3 cm/s . Part A What is the coefficient of static friction between the crate and the floor? μsμ s = nothing Request Answer Part B
Physics
1 answer:
iragen [17]3 years ago
8 0

Answer:

 μ = 0.725

Explanation:

This problem refers to Newton's second law.

       F = ma

Let's write the equations on each axis

Y Axis

      N-W = 0

     N = W

    N = mg

X axis

   F-fr = ma

With the body not started moving its acceleration is zero

  F-fr = 0

  F = fr

The friction force equation is

  fr = μ N

  fr = μ m g

Let's replace and calculate

   F = μ m g

   μ = F / mg

   μ = 321 /45.2 9.8

   μ = 0.725

You might be interested in
A flatbed truck is carrying a 20.0 kg crate along a level road. the coefficient of static friction between the crate and the bed
Dahasolnce [82]
<span>3.92 m/s^2 Assuming that the local gravitational acceleration is 9.8 m/s^2, then the maximum acceleration that the truck can have is the coefficient of static friction multiplied by the local gravitational acceleration, so 0.4 * 9.8 m/s^2 = 3.92 m/s^2 If you want the more complicated answer, the normal force that the crate exerts is it's mass times the local gravitational acceleration, so 20.0 kg * 9.8 m/s^2 = 196 kg*m/s^2 = 196 N Multiply by the coefficient of static friction, giving 196 N * 0.4 = 78.4 N So we need to apply 78.4 N of force to start the crate moving. Let's divide by the crate's mass 78.4 N / 20.0 kg = 78.4 kg*m/s^2 / 20.0 kg = 3.92 m/s^2 And you get the same result.</span>
6 0
3 years ago
HELP PLEASE 20 POINTS SHOW WORK, ALL EQUATIONS
nataly862011 [7]

Answer:

s = 3 m

Explanation:

Let t be the time the accelerating car starts.

Let's assume the vehicles are point masses so that "passing" takes no time.

the position of the constant velocity and accelerating vehicles are

s = vt = 40(t + 2)  cm

s = ½at² = ½(20)(t)² cm

they pass when their distance is the same

½(20)(t)² = 40(t + 2)

10t² = 40t + 80

0 = 10t² - 40t - 80

0 = t² - 4t - 8

t = (4±√(4² - 4(1)(-8))) / 2(1)

t = (4± 6.928) / 2  ignore the negative time as it has not occurred yet.

t = 5.464 s

s = 40(5.464 + 2) = 298.564 cm

300 cm when rounded to the single significant digit of the question numerals.

7 0
3 years ago
During a hurricane in 2008, the Westin Hotel in downtownNew Orleans suffered damage. Suppose a piece of glass dropped near the t
tangare [24]

Answer:

  • <u>77.8 m/s, downward</u>

Explanation:

For uniform acceleration motion, the average speed is equal to half the soum of the initial velocity, Vi, and the final velocity, Vf

  • Average speed = (Vf + Vi)/2

Also, by definition, the average speed is the distance divided by the time:

  • Average speed = distance / time

Then:

  • (Vf + Vi)/2 = 300m/6.62s

Other kinematic equation for uniform acceleration is:

  • Vf = Vi + a×t

Since the window is falling and the air resistance is ignored, a = g (gravitational acceleration ≈ 9.8m/s²)

Replacing the known values we can set a system of two equations:

From (Vf + Vi)/2 = 300m/6.62s

(Vf + Vi) = 2 × 300m/6.62s

  • Vf + Vi = 90.634      equation 1

From Vf = Vi + a×t

Vf - Vi = 9.8 (6.62)

  • Vf - Vi = 64.876     equation 2

Adding the two equations:

  • 2Vf = 155.510

  • Vf = 77.8 m/s downward (velocities must be reported with their directions)
8 0
3 years ago
What is the relationship between air pressure and air temperature?
LenKa [72]
The relationship between the two is that air temperature changes the air pressure. For example, as the air warms up the molecules in the air become more active and they use up more individual space even though there is the same<span> number of molecules. This causes an </span>increase<span> in the air pressure.</span>
8 0
3 years ago
The law of reflection states that if the angle of incidence is 39 degrees, the angle of reflection is ___ degrees.
marishachu [46]
It's 39 degrees, too


good luck
8 0
3 years ago
Other questions:
  • Children learn to resolve conflicts from surrounding adults.
    5·1 answer
  • A horizontal force of 50 N is applied to the object.
    15·1 answer
  • The main difference between speed and velocity involves
    9·2 answers
  • When the person is skating from the bottom of the track back up to the top, her potential energy _______ . When the person is sk
    7·1 answer
  • What is the energy of a photon of blue light with a wavelength of 460 nm?
    12·1 answer
  • Convert 37.45 kilometers to meters.<br> A.3745 m<br> B. 37,450 m<br> C. 3.745 m<br> D. 0.03745 m
    5·2 answers
  • Which could describe the motion of any object
    6·1 answer
  • PLEASE HELP<br> use the image to answer the question.<br> what is the name of the aluminum ion?
    11·2 answers
  • Multi celled organisms have a ______ surface area to volume ratio than single celled organisms.
    6·1 answer
  • The ball is dropped from a certain height and is falling to the ground. If its acceleration is a constant 9.8 meters per second
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!