Answer:
Los coeficientes de fricción estática y cinética son [tex]\frac{1}{15}[/tex] y [tex]\frac{1}{60}[/tex], respectivamente.
Explanation:
Por la Primera Ley de Newton, sabemos que la fuerza externa debe tener igual magnitud y dirección contraria a la fuerza de reacción (fricción). Puesto que el trineo se mueve sobre una superficie horizontal, la magnitud de la fuerza normal es la del peso ([tex]W[/tex]), en newtons. El coeficiente de fricción estática ([tex]\mu_{s}[/tex]), sin unidad, es la razón de la fuerza de fricción justo antes del movimiento inminente ([tex]F[/tex]), en newtons, a la fuerza normal ([tex]N[/tex]), en newtons:
[tex]\mu_{s} = \frac{F}{W}[/tex] (1)
Si sabemos que [tex]F = 40\,N[/tex] y [tex]W = 600\,N[/tex], entonces el coeficiente de fricción estática es:
[tex]\mu_{s} = \frac{F}{W}[/tex]
[tex]\mu_{s} = \frac{40\,N}{600\,N}[/tex]
[tex]\mu_{s} = \frac{1}{15}[/tex]
El coeficiente de fricción cinética ([tex]\mu_{k}[/tex]), sin unidad, es la razón de la fuerza de fricción experimentada por el trineo en movimiento ([tex]F[/tex]), en newtons, a la fuerza normal:
[tex]\mu_{k} = \frac{F}{W}[/tex] (2)
Si sabemos que [tex]F = 10\,N[/tex] y [tex]W = 600\,N[/tex], entonces el coeficiente de fricción cinética es:
[tex]\mu_{k} = \frac{F}{W}[/tex]
[tex]\mu_{k} = \frac{10\,N}{600\,N}[/tex]
[tex]\mu_{k} = \frac{1}{60}[/tex]
Los coeficientes de fricción estática y cinética son [tex]\frac{1}{15}[/tex] y [tex]\frac{1}{60}[/tex], respectivamente.
Which is closest to the Earth?
A. Moon
B. Sun
C. Mars
D. Venus
Answer:
A. Moon
Explanation:
The Moon is hundreds of thousands of miles away from the Earth while the other options are hundreds of millions of miles away.
Matter cant be created or destroyed
true
false
Answer: True
no matter can be created nor destroyed in any process. if something is burned, made in a compound or anything like that all matter is still the same amount from beginning to end.
Explanation:
skater spins over a point at a speed of 3.0 rotations per second then the momentum of inertia is 0.60 kg.M2, what is its angular momentum?
Answer:
[tex]L=11.3\ kg-m^2/s[/tex]
Explanation:
Given that,
Angular speed of a skater, [tex]\omega=3\ rot/s=18.84\ rad/s[/tex]
The moment of inertia of the skater, I = 0.6 kg-m²
We need to find the angular momentum of the skater. The formula for the angular momentum of the skater is given by :
[tex]L=I\omega[/tex]
Substitute all the values,
[tex]L=0.6\times 18.84\\\\L=11.3\ kg-m^2/s[/tex]
So, its angular momentum is equal to [tex]11.3\ kg-m^2/s[/tex].
define one ampere current electricity
Jack and Jill are pushing a 3 kg object on a rough surface; the object accelerates at a rate of 5 m/s2. Calculate the force applied by the Jack knowing that Jill is pushing 4 N and the rough surface applies 2 N force on the box as friction force.
Answer:
13 N
Explanation:
From the question,
(F₁+F₂)-F' = ma................ Equation 1
Where F₁= Jack's force, F₂ = Jill's force, F' = Friction force, m = mass of the object, a = acceleration of the object.
Given: F₂ = 4 N, F' = 2 N, m = 3 kg, a = 5 m/s²
Substitute these values into equation 1 and solve for F₁
(F₁+4)-2 = 3×5
(F₁+4)-2 = 15
F₁+4 = 15+2
F₁+4 = 17
F₁ = 17-4
F₁ = 13 N
Hence the force applied by Jack is 13 N
An electromagnet is a device that uses an electric current to produce a magnetic field.
Electromagnets are typically composed of a piece of metal wrapped with wire and connected to a battery. The battery provides the electric current, and the loops or coils of wire enhance the magnetic field. The more loops there are, the stronger the magnetic field.
When electric current flows through the electromagnet, the metal core becomes magnetized, so it possesses a north pole and a south pole.
Motors place electromagnets inside of permanent magnets as shown below.
However, motors are designed so that the polarity of the electromagnet constantly flips. That is, the north pole becomes the south pole, and the south pole becomes the north pole, every time the electromagnet turns 180 degrees.
Why is it designed this way?
A.
to conserve the energy in the battery
B.
to constantly polarize the field magnet
C.
so the electromagnet will continuously turn
D.
so the magnetic field will get stronger
The reason why motors are designed so that the polarity of the electromagnet constantly flips.is
C. so the electromagnet will continuously turn
Why is motor designed that wayThe reason motors are designed so that the polarity of the electromagnet constantly flips is to continuously turn the electromagnet. This allows the motor to rotate continuously, rather than becoming stuck in one position.
The flipping of the polarity causes the electromagnet to attract and repel from the permanent magnets, creating a rotating motion.
Therefore, the correct answer is C.
Learn more about motors at:
https://brainly.com/question/18619348
#SPJ1
You slide out of a car seat and as you touch the metal door a spark jumps between your hand and the door. Describe how the spark formed
Answer: Your body sliding against the car seat created friction, making it created potential energy. The friction is a form of electricity, and the car doors metal is a conductor of electricity. That potential energy was turned into kinetic once the metal attracted the electricity, thus making a spark.
Hope this helps ^_^
A rigid body of moment of inertia 0.5 kg.M^2 rotates with 2 RPM. How much torque is needed to increase the rotation to 10 RPM in 5 seconds.
Answer:
T = 0.084 Nm
Explanation:
First, we will calculate the angular acceleration:
[tex]\alpha = \frac{\omega_f - \omega_i}{t}[/tex]
where,
α = angular acceleration = ?
ωf = final angular speed = (10 RPM)(2π rad/1 rev)(1 min/60 s) = 1.05 rad/s
ωi = initial angular speed = (2 RPM)(2π rad/1 rev)(1 min/60 s) = 0.21 rad/s
t = time = 5 s
Therefore,
[tex]\alpha = \frac{1.05\rad/s - 0.21\ rad/s}{5\ s}\\\\\alpha = 0.168\ rad/s^2[/tex]
Now, for the torque:
[tex]T = I\alpha[/tex]
where,
T = torque = ?
I = moment of inertia = 0.5 kg.m²
Therefore,
[tex]T = (0.5\ kg.m^2)(0.168\ rad/s^2)\\[/tex]
T = 0.084 Nm
John often sees squiggly lines when he looks at a bright sky or white paper. His doctor says that they are called eye floaters, which are small bits of protein in the fluid that fills the eyeball.
In what part of the eye are eye floaters found?
a) cornea
b) vitreous humor
c) retina
d) convex lens
Answer- It's B, i double checked it on a few websites
The vitreous humor is the eye is eye floaters.
What is vitreous humor?The vitreous body (vitreous meaning "glass-like"; from Latin vitreus 'glassy', from vitrum 'glass', and -eus) is the clear gel that fills the space between the lens and the retina of the eyeball (the vitreous chamber) in humans and other vertebrates. It is often referred to as the vitreous humor (also spelled humour, from Latin meaning liquid) or simply "the vitreous". Vitreous fluid or "liquid vitreous" is the liquid component of the vitreous gel, found after a vitreous detachment. It is not to be confused with the aqueous humor, the other fluid in the eye that is found between the cornea and lens.
StructureThe vitreous humor is a transparent, colorless, gelatinous mass that fills the space in the eye between the lens and the retina. It is surrounded by a layer of collagen called the vitreous membrane (or hyaloid membrane or vitreous cortex) separating it from the rest of the eye. It makes up four-fifths of the volume of the eyeball.The vitreous humour is fluid-like near the centre, and gel-like near the edges.
Learn more about vitreous humor
https://brainly.com/question/14266481
#SPJ2
An object has a mass of 10grams and a volume of 20m3. what is the density of the object
Explanation:
density = mass/ volume
in the question the mass is given in grams so will convert it into kg,
10 g = 0.01 kg
density= 0.01/ 20 = 1 / 2000 = 0.005 kg/m^3
En una feria, se gana una jirafa de peluche lanzando una moneda a un platito, el cual está sobre una repisa más arriba del punto en que la moneda sale de la mano y a una distancia horizontal de 2.1 m desde ese punto (figura 3.41). Si lanza la moneda con velocidad de 6.4 m>s, a un ángulo de 60° sobre la horizontal, la moneda caerá en el platito. Ignore la resistencia del aire. A) ¿A qué altura está la repisa sobre el punto donde se lanza la moneda? B) ¿Qué componente vertical tiene la velocidad de la moneda justo antes de caer en el platito?
Answer:
A) La altura de la repisa sobre el punto donde se lanza la moneda es de aproximadamente 0,42 m
B) La velocidad de la moneda justo antes de que golpee el platillo es de aproximadamente 0,895 m/s hacia abajo
Explanation:
A) Los parámetros dados son;
La distancia horizontal del plato desde donde se lanza la moneda = 2,1 m
La velocidad con la que se lanza la moneda, u = 6,4 m / s
El ángulo al que se lanza la moneda, θ = 60 °
La componente horizontal de la velocidad, vₓ = 6.4 m / s × cos (60°) = 3.2 m/s
El tiempo que tarda la moneda en recorrer una distancia horizontal de 2,1 m, 't' se calcula de la siguiente manera;
t = 2,1 m/(3,2 m/s) = 0,65625 segundos
Por tanto, la altura de la moneda a 0,65625 segundos se da de la siguiente manera;
y = u × sin (θ) × t - (1/2) × g × t²
En t = 0,65625 segundos, obtenemos;
y = 6,4 × sin (60°) × 0,65625 - (1/2) × 9,81 × (0,65625) = 0,41840044589
La altura de la repisa sobre el punto donde se lanza la moneda, y ≈ 0.42 m
B) La velocidad vertical de la moneda justo antes de que golpee el platillo, [tex]v_y[/tex], se da como sigue;
[tex]v_y[/tex] = u × sin(θ) - g·t
∴ [tex]v_y[/tex] = 6.4 × sin(60°) - 9.81 × 0.65625 ≈ -0.895
La velocidad de la moneda justo antes de golpear el platillo, [tex]v_y[/tex] ≈ 0.895 m/s (hacia abajo)
help.....please science
Answer:
please mark me brainliest
Explanation:
ohm
The SI-derived unit of electric resistance is the ohm, which is defined as a volt per ampere.
Answer:
I cant see that
According to Hooke's law, the force exerted by a compressed or stretched spring is proportional to...
Answer:
Hooke's law can be written as:
F = -k*Δx
Where k is a constant that depends on the spring, called the spring constant.
And Δx = (x - x₀) is the displacement of the spring with respect to the rest position x₀
And a proportional equation is something like:
y = c*x
Where c is a constant of proportionality.
In the case of Hooke's law, the constant is K, then the force is proportional to the displacement of the spring with respect to the rest position Δx.
- Find the velocity of a wave in the ocean if the wavelength is 2.0m and the frequency is 0.56Hz.
Please please help
Bajo la acción del viento una puerta gira un ángulo de 90° en 5 s. Calcular su velocidad angular y la velocidad lineal de los puntos del borde
si el ancho de la puerta es de 50 cm. R. 0,314 rad/s, 0,157 m/s.
A 3kg object moving at 4 m/s encounters a 20 N resistive force over a duration of 0.20 seconds. The impulse experienced by this object is _____
Answer:
the impulse experienced by this object is 4 Ns
Explanation:
Given;
mass of the object, m = 3 kg
velocity of the object, v = 4 m/s
resistive force, F = 20 N
duration of impact, t = 0.2 s
The impulse experienced by this object is calculated as follows;
J = F x t
J = 20 x 0.2
J = 4 Ns
Therefore, the impulse experienced by this object is 4 Ns
What is density?
A- How much space an object takes
up
B- The amount of matter in a certain
amount of space
C- How much water an object
displaces
D- How much an object is affected by
gravity
Answer:
B- The amount of matter in a certain
amount of space
Explanation:
Density is the amount of matter an object has in a certain space. To find density, divide the mass of an object by the volume of an object.
Answer:
C- How much water it displaces
Explanation:
What type of specialized cell in the eye is used for detecting low levels of light?
Answer:
There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.
Answer:
Rods
Explanation:
There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.
A cat weighing 7 kg chases a mouse at a speed of 4 m/s. What is the kinetic energy of the cat?
a body falls freely from rest.calculate it's acceleration
Answer:
10 m/s²
Explanation:
Since the body is falling freely from the rest, it will be having an acceleration equal to the acceleration due to gravity.
∴ Acceleration = g = 9.8 m/s². ≈ 10 m/s².
Answer:
10 m/s^2 I hope it helps u a lot
How does refraction allow thin convex lenses to work?
Answer:
https://www.khanacademy.org/science/physics/geometric-optics/lenses/v/convex-lenses
Explanation:
Here is a link to a video to tell you about this.
True or False. The Magnitude of the induced voltage in a coil of wire depends on how quickly the magnetic flux through the coil of wire changes.
Answer:
Yes, its true
Explanation:
hdheheishdhieijzuwhs
Answer: yes its true
Explanation:
nmo
can someone please solve this
Answer:
The gravity is pulling the diver downwards but the rotation of the body means gravity cant pull him down as quickly
Explanation:
A child drops a bouncy ball. Each time it bounces, it reaches a lower height until it eventually
stops. Describe the energy transfers and explain why the ball lowered in height
Answer:
the ball's was lowered because of the gravitational force and because of the friction force's
How much work is done when 300 N of force is used to lift the dog 1.5 m?
Answer:
450N
Explanation:
Work done=Force*distance
a vehicle is moving with 20m/s towards the east and another is moving 15m/s towards the west
Answer:
5 m/s
Explanation:
Given that,
A vehicle is moving with 20m/s towards the east and another is moving 15m/s towards the west.
It is assumed to find the resultant velocity of the vehicle. Let east side is positive and west is negative. So,
[tex]v=v_1+v_2\\\\=20+(-15)\\\\=5\ m/s[/tex]
Hence, the resultant velocity of the vehicle is equal to 5 m/s.
A 1200 kg car accelerats from reat to 10.0 m/s in a time of 4.50 seconds. Calculate the force that thr car's tires exerted on the road.
Answer:
2667 N
Explanation:
Method 1: ImpulseWe can solve this problem by using the impulse formula.
FΔt = mΔv Δt = time interval, m = mass of the car (kg), Δv = change in velocityWe have three known variables, so we can solve for the fourth: F.
Divide Δt from both sides to isolate F.
F = (mΔv)/ΔtSubstitute known values into the equation.
F = [(1200 kg)(10 m/s - 0 m/s)] / 4.5 s F = [(1200)(10)]/4.5 F = 12000/4.5 F = 2666.666667 NThe force that the car's tires exert on the road is 2667 N.
Method 2: Newton's Second LawThe force that the car's tires exert on the road is equivalent to the force that the road exerts on the car due to Newton's Third Law of Motion.
We can calculate the force that the car's tires exert on the road by using the formula F = ma, which was derived from Newton's Second Law of Motion.
F = ma F = force exerted on the car, m = mass of the car (kg), a = acceleration of the car (m/s²)We are given the mass of the car, velocity of the car, and the time in which it accelerated.
We can use this equation for acceleration:
a = Δv/Δt Δv = final velocity - initial velocity (change in velocity), Δt = time intervalThe car started from rest, meaning it had an initial velocity of 0 m/s. Its final velocity was 10 m/s. The time that it took for the car to go from 0 m/s to 10 m/s was 4.5 seconds.
a = (10 m/s - 0 m/s) / 4.50 s a = 10/4.5 a = 2.222... m/s²Now we have two known variables, mass and acceleration. We can solve for the force exerted on the car (and thus, the force the car exerts on the road) using the formula F = ma.
F = ma F = (1200 kg)(2.222... m/s²) F = 1200 · 2.222...F = 2666.666667 NThe force that the car's tires exert on the road is 2667 N.
Determine the resistance of 100m of copper cable whose cross-sectional area is 1.5mm2
what is shot-curciting
Answer:
A path that allows most of the current in an electric circuit to flow around or away from the principal elements or devices in the circuit.
If a person meets an accident, which of the following factors will have more effect on his Kinetic energy and hence on the fatality of the accident?
A.velocity of the vehicle
B.Mass of the vehicle
Answer:
b
Explanation:
