A box of mass 60 kg is at rest on a horizontal floor that has a static coefficient of friction of 0.6 and a kinetic coefficient of 0.25
a)The minimum force necessary to start moving the box
b) The friction force and the acceleration of the box if a horizontal force of 400 N is applied
Answer:
a) F = 353.2 N
b) [tex]F_{f} = 147.2 N [/tex]
a = 4.21 m/s²
Explanation:
a) The minimum force necessary to start moving the box s given by:
[tex]\Sigma F = 0[/tex]
[tex] F - \mu_{s}N = 0 [/tex]
[tex] F = \mu_{s}mg [/tex]
Where:
F: is the force applied to move the box
μs: is the static coefficient of friction = 0.6
m: is the mass = 60 kg
g: is the gravity = 9.81 m/s²
[tex] F = 0.6*60 kg*9.81 m/s^{2} = 353.2 N [/tex]
b) The acceleration is:
[tex] F - F_{f} = ma [/tex]
[tex] F - \mu_{k}mg = ma [/tex]
[tex] a = \frac{F - \mu_{k}mg}{m} = \frac{400 N - 0.25*60 kg*9.81 m/s^{2}}{60 kg} = 4.21 m/s^{2} [/tex]
Now, the friction force is:
[tex] F_{f} = \mu_{k}mg = 0.25*60 kg*9.81 m/s^{2} = 147.2 N [/tex]
I hope it helps you!
Density Questions
How many blocks of ice-cream each 10cm x 10 cm x 4cm can be stored in the compartenent of a deep-freeze measuring 40 cm x 40cm x 20cm?
Explanation:
let's take the volume of each first:
ice cream: 10×10×4=400cm^3
freezer: 40×40×20=32,000cm^3
now we just divide: 32000/400=80
which is one characteristic of an electron?
Answer:
The electron is a negatively charged particle found in the atoms of all the elements. The electrons are located outside the nucleus in an atom. An electron is usually represented by the symbol (e –). The mass of an electron is about the mass of a hydrogen atom.
Explanation:
An electron with a total energy of 19GeV travels through an accelerator tube with proper length 7.7km. a) What is the length of the tube in the electron's frame? E= m b) How long does it take in the frame of the electron? E= s c) How long does it take in the frame of the tube? T= s Note: the rest energy of an electron is: 0=0.51MeV.
Answer:
a) Approximately 0.2066 m
b) 0.00002568443 s
c) Approximately 188.87 s
Explanation:
a) The total energy of the electron = 190GeV
The rest energy of the electron = 0.51 MeV
[tex]\dfrac{19 \ GeV}{0.51 \ MeV} = 37254.902 = \dfrac{1}{\sqrt{1 + \dfrac{u^2}{c^2} } }[/tex]
[tex]\left ( 1 - \dfrac{u^2}{c^2} \right ) = \dfrac{1}{37254.902^2} } }[/tex]
[tex]\left ( 1 - \dfrac{1}{37254.902^2} } } \right ) = \dfrac{u^2}{c^2}[/tex]
u = √(299792458² × (1 - 1/37254.902²)) = 299792457.892
β = v/c = 299792457.892/299792458 = 0.99999999964
[tex]\beta = \sqrt{1 - \left ( \dfrac{\Delta x}{\Delta x'} \right )^2}[/tex]
Δx = √(Δx'²×(1 - β²)) = √(7700²×(1 - 0.99999999964²)) ≈ 0.2066 m
The length of the tube in the electron's frame ≈ 0.2066 m
b) The time in the frame of the electron is given as follows;
Δt' = 7700/299792457.892 = 0.00002568443 s
c) The time in the frame of the tube is given as follows;
[tex]\beta = \sqrt{1 - \left ( \dfrac{\Delta t'}{\Delta t} \right )^2}[/tex]
1 - β² = (Δt'/Δt)²
Δt = √(Δt'/(1 - β²)) = √(0.00002568443 /(1 - 0.99999999964²)) ≈ 188.87 s.
A ball weighing 60 N is swinging like a pendulum at the end of a 6.0 m rope. As the
ball swings through its lowest point, its speed is measured at 5.0 m/s. What is the
tension in the rope at this point?
Answer:
Tension = 60 N
Explanation:
The ball is executing a motion like a pendulum. The lowest point of a pendulum's motion is the mean position, where its potential energy becomes zero and kinetic energy becomes maximum. At this point the rope becomes straight vertical. Hence, the tension in the rope becomes exactly equal to the weight of the object at the lowest point. Also, in this case when the ball swings through the lowest point during its motion like a pendulum, the tension in the rope will become equal to the weight of the ball.
Tension = Weight
Tension = 60 N
A falling object is said to reach a constant velocity (terminal velocity)..
a. when there is no gravitational force acting on it.
b. when there is no air resistance acting on it.
c. when air resistance equals the acceleration of gravity on it.
d. when it stops falling.
A baseball is thrown horizontally at a rate of 40m/s toward a home plate 18.4 m away. How far below the launch height is the ball when it reaches home plate
Answer:
1.03684mExplanation:
Using the formula for calculating range expressed as;
R = U√2H/g where
R is the distance moves in horizontal direction = 18.4m
H is the height
U is the velocity of the baseball = 40m/s
g is the acceleration due to gravity = 9.8m/s²
Substitute the given parameters into the formula and calculate H as shown;
18.4 = 40√2H/9.8
18.4/40 = √2H/9.8
0.46 = √2H/9.8
square both sides;
(0.46)² = (√2H/9.8)²
0.2116 = 2H/9.8
2H = 9.8*0.2116
2H = 2.07368
H = 2.07368/2
H = 1.03684m
Hence the ball is 1.03684m below the launch height when it reached home plate.
- A ball is thrown at a wall 50 meters away. It takes the ball 5 seconds to get to
the wall it is thrown at What is the average speed of the ball? SPEED
Answer:
The answer is 10 m/sExplanation:
The average speed of the ball can be found by using the formula
[tex]v = \frac{d}{t} \\ [/tex]
d is the distance
t is the time taken
From the question we have
[tex]v = \frac{50}{5} \\ [/tex]
We have the final answer as
10 m/sHope this helps you
5. What are the horizontal and vertical components of a 10 unit vector that is oriented 48
degrees above the horizontal?
Answer:
Fx = 6.69 [N]
Fy = 7.43 [N]
Explanation:
In order to solve this problem, we must remember that the x & y components of a vector can be determined using the cosine and sine function of the angle.
Fx = 10*cos (48) = 6.69 [N]
Fy = 10*sin (48) = 7.43 [N]
A 7 kg ball is moving at a constant speed of 5 m/s. A force of 300 N is applied to the ball for 4 s. The new speed of the ball is ?
Answer:
The new speed of the ball is 176.43 m/s
Explanation:
Given;
mass of the ball, m = 7 kg
initial speed of the ball, u = 5 m/s
applied force, F = 300 N
time of force action on the ball, t = 4 s
Apply Newton's second law of motion;
[tex]F = ma = \frac{m(v-u)}{t}\\\\m(v-u) = Ft\\\\v-u = \frac{Ft}{m}\\\\v = \frac{Ft}{m} + u[/tex]
where;
v is new speed of the ball
[tex]v = \frac{Ft}{m} + u\\\\v =\frac{300*4}{7} + 5\\\\v = 176.43 \ m/s[/tex]
Therefore, the new speed of the ball is 176.43 m/s
On the moon, the acceleration due to gravity is one-sixth that of earth. That is gmoon = gearth /6 = (9.8 m/s2 )/6 = 1.63 m/s2 . What effect, if any, would this have on the period of a pendulum of length L? How would the period of this pendulum differ from an equivalent one on earth?
¿Cuál será la potencia o consumo en watt de una ampolleta conectada a una red de energía eléctrica doméstica monofásica de 220 volt, si la corriente que circula por el circuito de la ampolleta es de 0,45 ampere?.
Answer:
La potencia o consumo en watt de una ampolleta conectada a una red de energía eléctrica doméstica monofásica de 220 volt, si la corriente que circula por el circuito de la ampolleta es de 0.45 ampere, es 99 Watts.
Explanation:
Potencia es la velocidad o rapidez con la que se consume la energía. Siendo la energía la capacidad que tiene un mecanismo o dispositivo eléctrico cualquiera para realizar un trabajo, también se puede definir potencia como la energía desarrollada o consumida en una unidad de tiempo. Su unidad de medida es el Watt.
La ley de Watt establece que la potencia eléctrica P suministrada por un elemento de circuito, es directamente proporcional al producto entre la tensión de la alimentación V del circuito y la intensidad de corriente I que circula por él.
Matemáticamente, la ley de Watt se expresa:
P = V.I
donde V es medida en Volt e I es medida en Ampere.
En este caso:
V=220 voltI= 0.45 ampereReemplazando:
P= 220 volt* 0.45 ampere
P= 99 Watts
La potencia o consumo en watt de una ampolleta conectada a una red de energía eléctrica doméstica monofásica de 220 volt, si la corriente que circula por el circuito de la ampolleta es de 0.45 ampere, es 99 Watts.
On a seismogram, higher lines drawn in the paper indicate weaker seismic waves.
True
False
True- just pick true
Explanation: it's true
A constant force pushes a 5 kg brick at 10 N. If the mass was tripled, what would happen to the acceleration if the same force is applied?
(PLEASE SHOW WITH STEPS)
Explanation:
The original acceleration is:
∑F = ma
10 N = (5 kg) a
a = 2 m/s²
If the mass is tripled, the new acceleration is:
∑F = ma
10 N = (15 kg) a
a = 0.67 m/s²
The acceleration is reduced by a factor of 3.
Answer:
1.35 miles per second
Explanation:
1 step it depende the way and hight he is
2 step the mass of the brick it depends
3 if it was triplet the acceleration it would be 1.50
What is the typical response of people to a government that abuses them if they are used to that government?
Answer:
when a government abuses its power its called tyranny and people might try to overthrow the government
do you think it’s likely that there are other earth-like planets in our universe?
Answer:
yes it's a matter of probability
Answer:
Absolutely!
Explanation:
Its almost impossible that we are the only goldilocks planet when there are billions of stars, each of them being suns with planets. Some other planet somewhere must be able to support life, don't you think?
Someone help me plz. I have no idea.
Answer:
fault im pretty sure
Explanation:
Answer:
fault............
...........
An object with a mass of 5 kilograms starts from rest and achieves a maximum speed of 10 meters per second in 0.5 seconds. What average unbalanced force on this object?
a. 50 N
b. 100 N
c. 10 N
d. 1000 N
Answer:
I think 1000 N............
ALWAYS use significant figure rules. Remember that these rules apply to all numbers that are measurements.
In working this problem, assume the value of "g" to be 9.8 m/s2 with two (2) significant digits unless otherwise stated.
A machine exerts a 100 N force to the right over a 5.00 meter length in 4.00 seconds. Calculate the power output of this machine.
_____ W
500.
125
80.0
0.200
Answer:
The answer is 500
Explanation:
In Stage 4 sleep, what type of brain waves do you have?
A. Delta
B. Beta
C. Spindle waves
D. Neural
a) the answer is delta waves i think
Answer:
A
Explanation:
There are screws all around you. Name five examples of screws that you see in everyday life? Think broadly!
Screw pump, Drill Machine, Bottle Caps, Faucets and Car Jack are the five examples of screws that we see in everyday life.
What is screw?Screw is defined as a short, sharp-pointed metal pin with a raised helical thread present round it. It has a slotted head that is used to join things together by rotating it so that it pierces wood and is held tightly on its place. Screw is used in many materials in order to join two frames or bodies with each other. Without this screw, we can't imagine many materials to work together so screw has very high importance.
So we can conclude that Screw pump, Drill Machine, Bottle Caps, Faucets and Car Jack are the five examples of screws that we see in everyday life.
Learn more about screw here: https://brainly.com/question/9620666
#SPJ1
A person weighing 600N runs up a flight of stairs. It takes the person 10s to get to the top. They are 6m higher at the top of the stairs. How much power was used?
Answer:
[tex]Power = 360W[/tex]
Explanation:
Given
[tex]Force = 600N[/tex]
[tex]Time = 10s[/tex]
[tex]Height = 6m[/tex]
Required
Determine the power used
First, we need to calculate the work done to climb the stairs.
[tex]Word = Force * Distance[/tex]
In this case, the distance represents the height of the stairs.
So:
[tex]Work = 600N * 6m[/tex]
[tex]Work = 3600J[/tex]
Next, we calculate the power using:
[tex]Power = \frac{Work}{Time}[/tex]
Substitute values for Work and Time
[tex]Power = \frac{3600J}{10s}[/tex]
[tex]Power = 360W[/tex]
Hence, the power used by the person is 360 watts
Two metallic rods A and B of different materials have same length. The linear expansivity of A is 12×10–6 oC–1and cubical expansivity of B is 24×10–6 oC–1. If both rods are heated from 20oC to 100oC, the length of rod A will be....................... The length of rod B.
Answer:
The length of rod A will be greater than the length of rod B
Explanation:
We, know that the formula for final length in linear thermal expansion of a rod is:
L' = L(1 + ∝ΔT)
where,
L' = Final Length
L = Initial Length
∝ = Co-efficient of linear expansion
ΔT = Change in temperature
Since, the rods here have same original length and the temperature difference is same as well. Therefore, the final length will only depend upon the coefficient of linear expansion.
For Rod A:
∝₁ = 12 x 10⁻⁶ °C⁻¹
For Rod B:
∝₂ = β₂/3
where,
β₂ = Coefficient of volumetric expansion for rod B = 24 x 10⁻⁶ °C⁻¹
Therefore,
∝₂ = 24 x 10⁻⁶ °C⁻¹/3
∝₂ = 8 x 10⁻⁶ °C⁻¹
Since,
∝₁ > ∝₂
Therefore,
L₁ > L₂
So, the length of rod A will be greater than the length of rod B
which characteristic is related to kinetic energy but not potential energy.
A. an objects mass
B. an objects speed
C. an objects shape
D. an objects height
Answer:
Option (D)
Explanation:
What is the average speed of a car that traveled for 192.5 miles in 3.5 hours?
Answer:
55miles per hour
Explanation:
speed=distance/time
speed=192.5miles/3.5hours
speed=55miles per hour
Answer:
55miles per hour
Explanation:
Simply divide the number you travelled with the hour you will get the answer.
Why are wildfires getting worse ? Does is have to do with Climate Change ?
Answer:
There is a logical explanation for that.
Explanation:
Human activities such as lighting campfires and discarding lit cigarettes are responsible for starting fires, hotter weather makes forests drier and more susceptible to burning.
Rising temperatures, a key to climate change, evaporate moisture from the ground, drying out the soil, and making vegetation more flammable. At the same time, winter snowpacks are melting a month earlier, meaning forests are drier for longer periods.
As drought and rising heat continue with rising greenhouse gas emissions, there will be more expected wildfires in the years ahead, especially with the fire seasons getting longer.
What is the Net Force acting
on the box below?
Question 18 (2 points)
A supersonic jet flying at 100 m/s is accelerated uniformly at the rate of 20 m/s2 for 20 s. What is its final velocity?
kinetic energy is energy in the form of motin
Answer:
yes
Explanation:
Una persona de 80 kg de masa corre a una velocidad cuya magnitud es de 9m/s. Cual es la magnitud de la cantidad de movimiento? Que magnitud de velocidad debe llevar una persona de 55 kg para tener la misma magnitud de la cantidad de movimiento que la persona de 80 kg?
Responder:
13,01 m / s
Explicación:
Paso uno:
datos dados
masa de la persona 1 m = 80 kg
velocidad de la persona 1 v = 9 m / s
masa de la persona 2 M = 55kg
velocidad de la persona 2 v =?
Segundo paso:
la expresión del impulso se da como
P = mv
para la primera persona, el impulso es
P = 80 * 9
P = 720N
Paso tres:
queremos que la segunda persona tenga el mismo impulso que la primera, por lo que la velocidad debe ser
720 = 55v
v = 720/55
v = 13,09
v = 13,01 m / s
Por lo tanto, la magnitud de la velocidad debe ser 13.01 m / s.