Answer:
μ = 0.179
Explanation:
For this exercise we use the rotational equilibrium condition, where we set a reference system at the top of the ladder where it is in contact with the parent, we will assume the counterclockwise rotations as positive
∑ τ = 0
W_stairs x/2 + W_man x’+ fr y - N x = 0
fr y = -W_stairs x/2 - W_man x’ + N x
let's use trigonometry for distances
* the man up the ladder 78%
l ’= 0.78 L
cos 59 = x ’/ l’
x’= 0.78 L cos 59
* the horizontal distance
cos 59 = x / L
x = L cos 59
* vertical distance
sin 59 = Y / L
y = L sin 59
we substitute
fr L sin 59 = -W_stairs Lcos59 / 2 - W_man 0.78 L cos59 + N L cos59
fr sin 59 = - ½ W_stairs cos 59 - 0.78 W_man cos 59 + N cos 59
fr = ctan 59 (N - ½ W_stairs - 0.78 W_man) (1)
Let's write the translational equilibrium equations
Y axis
N -W_stairs - W_man = 0
N = W_stairs + W_man
N = 85 + 21.5 9.8
N = 295.7 N
we substitute in 1
fr = ctg 59 (295.7 - ½ 85 - 0.78 21.5 9.8)
fr = 0.6 (295.7 - 42.5 - 164.346)
fr = 52.89 N
the expression for the friction force is
fr = μ N
μ = fr / N
μ = 52.89 / 295.7
μ = 0.179
which line represnts object moving fastest
**WILL MARK BRAINLEST ANSWER, IF RIGHT**
Line - A: (15/10) = 1.5 inch/second
Line - B: (0/10) = 0
Line - C: (10/10) = 1.0 inch/second
Line - D: (-25/20) = -1.25 inch/second
Line-A represents the greatest speed.
If I keep F constant in F=ma, what is the relationship between m and a?
Answer:
If F is a constant, we can take f = 1
f = m×a
ma = 1
therefore we can say that force is hence proportinal to the product of mass and acceleration.
A stone of mass 0.2kg is thrown vertically upwards from the ground with a velocity of 20m/s. Find the maximum height attained by the stone
Answer: 20.4 m
Explanation: speed v upward is v = vo -gt.
When maximum height v = 0, vo -gt = 0 and
T = vo / g = 20 m/s / 9.81 m/s² = 2.04 s
Now height y = vot -0.5 gt^2 = 20,4 m
This is possible to solve using
Conservation of energy Ek= Ep
0.5mv² = mgh. And h = v²/2g. Results same
A 2kg rock is dropped from a height of 10m and hits the ground going 11m/s. How much work was done by air resistance as it fell?
Answer: 0.24 kg/m
Explanation: use k = ρ * A * C / 2 as the formulaA car goes East from 2 m/s to 16m/s in 3.5s. What is the Car's acceleration?
What is the unit of energy called? (Give name and symbol)
Don't scroll down. Help pls 22 POINTS!!
Answer:
I don't know if these are all right but these are my best answers. good luck and I hope you do well.
1. true
2. true
3. false
4. true
5. true
6. true
7. true
8. true
9. false
10. false
13. it stimulates the heart through chest compressions
14. on bare skin upper right shoulder and lower left ribs
15. no CPR
Explanation:
If the cells in a circuit are the wrong way around
why does it not work
2 mark explanation
I will mark brainliest
Answer:
By sarting it right and explain
Answer:
There is no current in a diode (in the reverse diode)
Explanation:
Charge willl not flow through a diode (in the reverse directiom)
BECAUSE A DIODE HAS A VERY HIGH RESISTANCE IN THE REVERSE DIRECTION
Giving Brainliest
Please help, Stay Safe and healthy
Answer: A I think
Explanation:
HELP PLEASE!!!!!!!!!!!!!!!
A silver tea spoon is placed in a cup filled with hot tea. After some time, the exposed end of the spoon becomes hot even without a
direct contact with the liquid. This phenomenon can be explained by:
Answer:
As atoms in the spoon vibrates about their equilibrium positions and transfer energy form one end to other end. This process is called conduction.
why the friction between an object and a surface is less than when the surface is titled than when the same surface is horizontal
Answer:
nvjch
ffufuxuhxjcjfbfdhdh
Hey guys, can you please help me with this question?
A rectangular container of base 50 cm by 30 cm is filled with water to a depth of 5 cm. How much is the pressure exerted at the base? (Take p= 1000 kg/m3 and g=10m/s)
Answer:
the pressure exerted at the base of the container is 490 N/m²
Explanation:
Given;
density of water, ρ = 1,000 kg/m³
base of the rectangular container, = 50 cm by 30 cm
height of water in the tank, h = 5 cm = 0.05 m
The pressure exerted at the base of the container is calculated as;
P = ρgh
where;
g is acceleration due to gravity = 9.8 m/s²
P = 1000 x 9.8 x 0.05
P = 490 N/m²
Therefore, the pressure exerted at the base of the container is 490 N/m²
To drive your car from Auburn to Atlanta (173.8 km) takes a significant amount of work. Assuming the force of friction between the tires and the road is 10290 N, how much work needed to drive that far? Express your answer in megajoules (MJ).
Answer:
1788.402 MJ
Explanation:
Work done = Force (N) x distance (m)
First we have to convert distance into metres:
173.8 x 1000 = 173,800 m
Then plug these values into the equation above:
173,800 x 10290 = 1788402000 J
The reason it's Joules (the unit for energy) is because work done = energy transferred
Now we have to convert Joules into Mega Joules:
1 J = 1/1000000 MJ
1788402000 J = 1788402000/ 1000000 = 1788.402 MJ
6. _______________ : when a certain number of waves pass a given point for a certain number of seconds? Group of answer choices A. wavelength C. amplitude D. height B. frequency
Ill give brainly-ist.
Answer:
b
kakanandnanjsnMajdnAnnznnzkkzid
Answer:
Frequency
Explanation:
I just took that test
a race car driving around the road is unbalanced or balanced?
Answer:
balenced
Explanation:
Which chemical change describes the reactions of elements and compounds that, in general, do not involve carbon and typically take place in laboratories or industries?
Answer:
Inorganic.
Explanation:
The chemical change which describes the reactions of elements and compounds that, in general, do not involve carbon and typically take place in laboratories or industries is inorganic.
In Chemistry, an inorganic chemical reaction can be defined as a type of chemical reaction that occurs without a carbon-hydrogen bond.
On the other hand, organic chemistry deals with reaction that occur in the presence of carbon-hydrogen bonds such as hydrocarbons.
A particle was moving in a straight line at 172.8 km/hr. If it decelerated over 120 meters to come to rest, find the time taken to cover this distance.
Answer:
v=s/t
s=vt
t=s/v
t=(120×10‐³)/172.8
(the distance meters has been changed to kilometres)
t=1/1440 hrs
Given ,
please help meeee, I need help to complete my assignment
Does an object of a higher mass absorb more thermal energy than an object of lower mass?
A wave with a wavelength of 4.0 m has a frequency of 2 Hz. Calculate the speed of this wave.
O 2 m/s
O 8 m/s
O 6 m/s
O 0.5 m/s
Answer:
8m/s
Explanation:
because frequency×wavelength
The tuning fork has a frequency of 426.7 is found to cause resonance in a closed column of air measuring 0.186 (the diameter of the tube is 0.015m) find the velocity of the sound produced by the tuning fork.
Answer:
The velocity of the tuning fork sound is 317.4648 m/s
Explanation:
The given parameters are;
The frequency of the fork, f = 426.7 Hz
The length of the closed air column, L = 0.186 m
The diameter of the tube, d = 0.15 m
At the fundamental frequency in a closed tube, we have;
λ = 4·L
Where;
λ = The wavelength of the wave
L = The length of the tube
From the equation for the velocity of a wave, we have;
v = f·λ
Where;
v = The velocity of the (sound) wave
f = The frequency of the wave = 426.7 Hz
λ = 4·L = 4 × 0.186 m = 0.744 m
∴ v = 426.7 Hz × 0.744 m = 317.4648 m/s
Therefore, the velocity of the sound produced by the tuning fork, v = 317.4648 m/s
work and power!!
____is the measure of how much work, energy, or power is used or converted properly. Efficiency C Power b Newton d. Horsepower
Answer:
Efficiency
Explanation:
A 2 column table with 4 rows. The first column is labeled substance with entries W, X, Y, Z. The second column is labeled temperature in degrees celcius with entries 40, 37, 19, 37.
Which statement is best supported by the data in the chart?
Answer:
B
Explanation:
Answer:
B. is the correct option! The person above was correct :)
Explanation:
Have a great day!
Some people today claim the Earth is flat. Produce an argument to prove that the
Earth is not flat.
Answer:
i mean i think it is. we have no real pics of the earth they are all fake. And the moon landing was fake. the usa flag was blowing but there is no wind in space . its all fake
Explanation:
What is the transfer of energy that occurs when a force causes an object to move?
O Energy
Force
Power
O Work
Answer:
huh? I think it's Power.....
Please help!!! what is the main point of paragraph 3?
Una muestra de agua de 250g de agua se caliento desde 10°C hasta 60°C calcula la cantidad de calor absorbido por el agua el calor especifico del agua es de 4186J/Kj.K
Answer:
Calor absorbido, Q = 52325 Joules
Explanation:
Dados los siguientes datos;
Masa = 250g to kg = 250/1000 = 0.25kg
Temperatura inicial, T1 = 10°C to Kelvin = 273 + 10 = 283K
Temperatura final, T2 = 60°C to Kelvin = 273 + 60 = 333K
Capacidad calorífica específica = 4186 j/kg.K.
Para encontrar la cantidad de calor necesaria;
La capacidad calorífica viene dada por la fórmula;
[tex] Q = mct [/tex]
Dónde;
Q representa la capacidad calorífica o la cantidad de calor.
m representa la masa de un objeto.
c representa la capacidad calorífica específica del agua.
dt representa el cambio de temperatura.
dt = T2 - T1
dt = 333 - 283
dt = 50 K
Sustituyendo en la fórmula, tenemos;
[tex] Q = 0.25*4186*50[/tex]
[tex] Q = 52325 [/tex]
Calor absorbido, Q = 52325 Joules
What causes "changing" motion?
Balanced forces
Unbalanced Forces
Steady Motion
The force
Answer:listen to class
Explanation:
-1
Answer:
Unbalanced Forces
Explanation:
According to the Newton's First law, it states that an object either remains at rest or continues to move at a constant velocity, unless it is acted upon by an external force. The answer is Unbalanced Forces
a) A 12 kg object has a velocity of 37.5 m/s. What is its momentum?
b) How far does it get in 16 s?
Answer:
The answer would be 450 m kg/s
Explanation/ Explanation / Example:
Provided an object traveled 500 meters in 3 minutes , to calculate the average velocity you should take the following steps: Change minutes into seconds (so that the final result would be in meters per second). 3 minutes = 3 * 60 = 180 seconds , Divide the distance by time: velocity = 500 / 180 = 2.77 m/s .
If this doesn't help let me know!
If a scientist is designing a device to create high energy electromagnetic waves, which type of wave would the device most likely create?
А
microwaves
B
infrared waves
с
ultraviolet waves
D
gamma ray waves