Answer:
he gravity of Earth, denoted by g, is the net acceleration that is imparted to objects due to the combined effect of gravitation (from mass distribution within Earth) and the centrifugal force (from the Earth's rotation )
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
When a substance is poured from one container to another, its shape changes but its volume does not, what state of matter is the substance in?
A. Plasma
B. Liquid
C. Gas
D. Solid
Answer: When a liquid substance is poured into a vessel, it takes the shape of the vessel, and, as long as the substance stays in the liquid state, it will remain inside the vessel. Furthermore, when a liquid is poured from one vessel to another, it retains its volume (as long as there is no vaporization or change in temperature) but not its shape.
Explanation: A solid has a definite shape and volume. A liquid has a definite volume, but takes the shape of its container. A gas lacks either a defined shape or volume. Plasma is similar to a gas in that its particles are very far apart, but a gas is electrically neutral and plasma has a charge.
Answer:
B
Explanation:
Liquid
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.
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
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
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:
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
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
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:
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
Determine the resistance of 100m of copper cable whose cross-sectional area is 1.5mm2
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.
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
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
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:
What is only found in plant cells??
Cell membrane , nucleus, cell wall , vacuole.
which one !!!
Help!!!
Where can the hoses be attached in order to provide water to a fire engine? (There may be more than one correct answer.)
house faucet
hydrant
generator
pumper truck
Answer:
Explanation:
Hydrant
- Find the velocity of a wave in the ocean if the wavelength is 2.0m and the frequency is 0.56Hz.
Please please help
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.
define one ampere current electricity
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 ^_^
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.
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].
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.
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 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.
When a bouncy ball is dropped from a second floor window, at what point is the kinetic energy highest?
A. Just after the ball dropped
B. Just before the ball hits the ground for the first time
C. After the ball has bounced several time
D. after the ball bounces away into the bushes, never to be found again
Answer:
Explanation:
Because the total energy available to the ball doesn't change whatsoever during its entire trip from the window to the ground,
TE = KE + PE which says that the total energy available to a system is equal to the kinetic energy of the system plus the potential energy, and that this value will not ever change (because energy cannot be created or destroyed. Sound familiar?) If the ball is being held still before it is dropped from some height off the ground, it is here that the total energy can be determined, and that total energy at this point is all potential, since the ball is not moving while someone is holding it and getting ready to drop it. The SECOND it starts to fall, the potential energy begins to be converted to kinetic. As the potential energy is losing value, the kinetic is gaining it at the same rate (again, energy doesn't just disappear; it has to go somewhere. Here, it goes from potential to kinetic a little at a time). When the ball finally hits the ground, or an INSTANT BEFORE it hits the ground, the potential energy is 0 because the height of something on the ground has a height of 0. At this instant, right before the ball hits the ground, is where the KE is the greatest. All the energy at that point has been converted from potential to kinetic.
Long story short, choice B is the one you want.
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.
An object's velocity/speed increases, multiplied by a factor of 7. What factor would its Kinetic Energy increase by?
Answer:
k.E= 49 ms^-2
Explanation:
k.E= 1/2 mv^2
From that formula of k.E
K.E is directly proportional to the ( velocity)^2
K.E directly proportional to (7)^2
so that k.E increase by 49
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
