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
likoan [24]
2 years ago
12

A 6 m long, uniform ladder leans against a frictionless wall and makes an angle of 74.3 ◦ with the floor. The ladder has a mass

25.8 kg. A 67.08 kg man climbs 82% of the way to the top of the ladder when it slips and falls to the floor. What is the coefficient of static friction be- tween the ladder and the floor?
Physics
1 answer:
olganol [36]2 years ago
4 0

Answer: µ=0.205

Explanation:

The horizontal forces acting on the ladder are the friction(f) at the floor and the normal force (Fw) at the wall. For horizontal equilibrium,

f=Fw

The sum of the moments about the base of the ladder Is 0

ΣM = 0 = Fw*L*sin74.3º - (25.8kg*(L/2) + 67.08kg*0.82L)*cos74.3º*9.8m/s²

Note that it doesn't matter WHAT the length of the ladder is -- it cancels.

Solve this for Fw.

0= 0.9637FwL - (67.91L)2.652

Fw=180.1/0.9637

Fw=186.87N

f=186.81N

Since Fw=f

We know Fw, so we know f.

But f = µ*Fn

where Fn is the normal force at the floor --

Fn = (25.8 + 67.08)kg * 9.8m/s² =

910.22N

so

µ = f / Fn

186.81/910.22

µ= 0.205

You might be interested in
A solid cylinder of mass 7 kg and radius 0.9 m starts from rest at the top of a 20º incline. It is released and rolls without sl
ohaa [14]

Answer:

157.8 J

Explanation:

m = mass of the cylinder = 7 kg

h = height difference in top and bottom of the incline = 2.3 m

g = acceleration due to gravity = 9.8 m/s²

TE = Total Energy at the bottom

PE = Gravitational potential energy at the top

Using conservation of energy

Total Energy at the bottom = Gravitational potential energy at the top  

TE = PE

TE = m g h

TE = (7) (9.8) (2.3)

TE = 157.8 J

7 0
2 years ago
Energy created by the flow of electrons through a conductor.
kodGreya [7K]
The first one is electrical energy
3 0
2 years ago
a man exerts 700 newtons of force to move a piece of furniture 4 meters. if it takes him 2 seconds to move the furniture, how mu
dybincka [34]

                               Work = (force) x (distance)

The work he did:    Work = (700 N) x (4m)  =  2,800 joules

The rate at which
he did it (power):    Work/time =  2,800 joules/2 sec

                                                =  1,400  joules/sec

                                                =  1,400 watts

                                                =  1.877... horsepower (rounded)
 
6 0
2 years ago
At what point in its motion is the KE of a pendulum bob a maximum? 1. The KE does not change. 2. at the lowest point 3. at the h
Andrew [12]

Answer:

2. at the lowest point

Explanation:

The motion of the pendulum is a continuous conversion between kinetic energy (KE) and gravitational potential energy (GPE). This is because the mechanical energy of the pendulum, which is sum of KE and GPE, is constant:

E = KE + GPE = const.

Therefore, when KE is maximum, GPE is minimum, and viceversa.

So, the point of the motion where the KE is maximum is where the GPE is minimum: and since the GPE is directly proportional to the heigth of the bob:

GPE=mgh

we see that GPE is minimum when the bob is at the lowest point,so the correct answer is

2. at the lowest point

3 0
3 years ago
PLS HELP !!
Ira Lisetskai [31]
A because it’s basic kinetic example
4 0
2 years ago
Read 2 more answers
Other questions:
  • As an emergency vehicle approaches Bob and moves away from Jill, how does the actual frequency of the siren change? A) As an eme
    5·1 answer
  • As the kinetic energy of an object increases, so does the _________ energy produced. A) heat B) light C) atomic D) potential
    7·2 answers
  • A moving curling stone, A, collides head on with stationary stone, B. Stone B has a larger mass than stone A. If friction is neg
    13·1 answer
  • What W is the amount of force with which gravity is pulling down on something<br>​
    6·1 answer
  • Electromagnetic waves are not mechanical waves, which means they can<br> travel in a:
    13·1 answer
  • Write an essay about the things an individual must do in order to adapt and survive the changes that are happening in his/her en
    12·1 answer
  • If an object had a negative velocity, then it must be traveling<br>North<br>Up<br>East<br>South​
    12·1 answer
  • Help please :)<br><br> Infrared waves are transmitted by ....... ?
    7·2 answers
  • A push on a 1-kg brick accelerates it. Neglecting friction, equally accelerating a 10-kg brick requires 10 times as much force.
    11·1 answer
  • Two astronauts of mass 100 kg are 2 m apart in outer space. What is the
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!