Answer:
B. A magnet is necessary to produce a permanent magnetic field.
Explanation:
When building a simple motor, a permanent magnet is necessary to produce a magnetic field in which opposite North South polarity which will help in rotating the main copper core when the battery is connected.
What type of modulation is typically used by broadcasting stations to transmit pictures on television screens?
Isaac Newton's first law of motion states?
Answer:
His first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. In other words its inertia.
Explanation:
Newtons first law of motion states that"A body will continue to its state of rest or motion unless external force acted upon it.
value of i cap,j cap, k cap
Answer:
i cap is the unit vector for x axis
eg 2 i cap
j cap is the unit vector for y axis
eg 3 j cap
hope it will help you
Explanation:
Jacki evaluated the expression below. 2 cubed (3 minus 1) + 4 (8 minus 12) = 2 cubed (2) + 4 (4) = 8 (2) + 16 = 16 + 16 = 32. What was Jacki’s error? Jacki should have simplified the exponent first. Jacki should have multiplied 4 and 8 first. Jacki did not subtract 12 from 8 correctly. Jacki should not have multiplied 8 and 2.
Answer:
Her error was that she did not subtract 12 from 8 correctly
Explanation:
Jackie did 8-12 instead of 12-8
Which of the following statements is true of inertia?
(1 Point)
Inertia is a force
Inertia is a force which keeps stationary objects at rest and moving objects in motion at constant velocity.
Inertia is a force which brings all objects to a rest position.
A more massive object has more inertia than a less massive object.
Options A, B & D are true.
We are dealing with the concept of inertia.
From Newton's first law of motion which is referred to as law of inertia, we are told that; An object will remain at rest or continue in constant motion unless it is acted upon by an external force.This means that inertia is the force that keeps an object at rest or in constant motion.
Furthermore, it means that the bigger the object, the more the inertia because a bigger object will require more force to make it move from rest.Looking at the options, the only option that doesn't correspond with definition of Inertia is Option C. Options A, B and D are true based on our explanation above.Read more at; brainly.com/question/13656225
What would happen if you put a material between each marble? Newton's Cradle
Answer:
Explanation:
Momentum is the mass of a moving body times its velocity. It can be transferred from one object to another
Determine the components, the magnitude and the angle (counter-clockwise with respect to the positive x axis) of the resultant vector, R = B + C. Given: 0 Vector B: magnitude = 5.00 units, angle = 115 . 0 Vector C: magnitude = 4.00 units, angle = 255 .
Answer:
Explanation:
We shall represent vector B and C in terms of i and j .
B = 5 cos115 i + 5 sin115 j
= -2.11 i + 4.53j
Similarly
C = 4 cos255 i + 4 sin225 j
= -1.04 i -3.86 j
R = B + C
= -2.11 i + 4.53j -1.04 i -3.86 j
= -3.15 i + .67 j
magnitude of R
= √( 3.15² + .67² )
= √( 9.92 +.45 )
= 3.22
Angle Ф
TanФ = - .67 / 3.15
= - .21
Ф = - 12⁰
= 180 - 12
= 168 degree counterclockwise from positive x axis.
Which type of lens produces diverging rays?
A) Concave Lens
B) Convex Lens
C) Concave Mirror
D) Flat Mirror
Answer:
The fact that a double concave lens is thinner across its middle is an indicator that it will diverge rays of light that travel parallel to its principal axis. A double concave lens is a diverging lens.
A candle’s wick is the fabric string that holds the flame, and it burns down at a constant slow pace when the candle is lit. The wick is usually surrounded by wax. Which is the most important property of covalent compounds that makes them useful for making candle wax? a low boiling point a low melting point a high boiling point a high melting point
Answer:
the answer is a low melting point
Explanation:
on edge
Low melting point is the most important property of covalent compounds that makes them useful for making candle wax.
A molecule created by covalent bonding whereby the atoms possess one or much more pair of valence electrons is referred to as a covalent compound. Covalent compounds or ionic compounds are the two groups into which chemical compounds are often divided.
Ionic compounds are composed of atoms or molecules that have gained or lost electrons, causing them to become electrically charged. Ionic compounds are created when ions with opposing charges come together, typically when a metal interacts with a nonmetal. Low melting point is the most important property of covalent compounds that makes them useful for making candle wax.
To know more about covalent compound, here:
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When carrying passengers up to the second floor, an escalator does 3,000 Nm of work. The time it takes the
escalator to move to the second floor is 6 seconds. The power of the escalator is
Nm/s.
Answer:
500Nm/s
Explanation:
500
this is the Plato answer!!!!!!
Please Help!! This is very tough for me. Try you best to answer these problems!!Pleaseee
Answer:
everyone else does this to me so lol
Explanation:
Answer:
1. 9 m/s/s
2. 33 m/s
3. 5 m/s/s
4. 9.6 m/s
Explanation:
What Is The Definition Of Friction?
A firefighter of mass 75 kg slides down a pole. The force of friction is 400N. What is the firefighter's acceleration as they slide down the pole?
Answer:
a = 5.33 [m/s²]
Explanation:
To solve this problem we must use Newton's second law which tells us that the sum of the forces acting on a body is equal to the product of mass by acceleration.
ΣF = m*a
where:
F = force = 400 [N]
m = mass = 75 [kg]
a = F/m
a = 400/75
a = 5.33 [m/s²]
Sienna made a chart listing the steps that describe how a four-stroke heat engine operates.
COM
Step
1
Name
intake
2
ignition
Description
piston moves down and fuel-air mixture
enters cylinder
spark plug fires and causes combustion,
leading to gas expansion
piston moves up and temperature of gas
increases
piston moves up, pushing burned gas
through exhaust valve
3
compression
4
exhaust
Which best describes Sienna's error?
o The descriptions for intake and ignition should be switched with one another.
O During compression, temperature does not increase, it decreases.
O Compression happens before ignition, so it should be step 2.
O The piston moves down, not up, during the exhaust step.
Answer:
C
Explanation:
Answer:
c
Explanation:
e2020
Can you hellp me please
Answer:
the answer is C
Explanation:
because the moon has to be in front of the sun hope this helps
Explanation:
may be (C) is the correct answer .
Is CO2 is a molecule or a element or a compound
Answer:
Compound
Explanation:
Answer:
Compound
Explanation:
Its molecules consist of one carbon atom joined to two oxygen atoms. If you have more than one element chemically bonded, it is a compound.
Oysters are filter feeders. They get their food by moving large amounts of water through their bodies and filtering out whatever is in it. They eat plankton, algae, and similar things that they find in the water. They also remove dirt and chemicals that they find in the water.
How do oysters help other things that live in the water with them?
A.
by removing harmful substances from the water
B.
by removing food from the water
C.
by adding air to the water
D.
all of these
A. Oysters, clams, and other shellfish are efficient filter feeders that help remove excess nitrogen from waters by incorporating it into their shells and tissue as they grow. ... Adult oysters reportedly can filter up to 50 gallons a day, while large quahogs (hard clams) can clean about 24 gallons of water a day
Using your Texting and Driving Spreadsheet: Velocity of the Car: 10 m/s Time of distraction: 8.0 sec Time of reaction: 0.5 sec Velocity after braking: 0.0 m/s Deceleration due to braking: -8.0 m/s/s Warm Up If roads were icy: 1. What would you change in the inputs above and why? ____________ Now, what is: 2. Distance while distracted:_______ m 3. Distance while reacting: _______ m 4. Time while braking: _______ sec 5. Distance while braking: _______ m 6. Total distance: _______ m
Answer:
1. I would like to change the time of distraction. Because 8 s is a long time to be distracted while driving on the road. Its not safe for the driver and the other people on road if the driver is distracted even for a second.
2. s₁ = 80 m
3. s₂ = 5 m
4. t = 1.25 s
5. s₃ = 7.5 m
6. s = 92.5 m
Explanation:
1.
I would like to change the time of distraction. Because 8 s is a long time to be distracted while driving on the road. Its not safe for the driver and the other people on road if the driver is distracted even for a second.
2.
Distance Covered While Distracted = s₁ = (speed of car)(distraction time)
s₁ = (10 m/s)(8 s)
s₁ = 80 m
3.
Distance Covered While Reacting = s₂ = (speed of car)(reaction time)
s₂ = (10 m/s)(0.5 s)
s₂ = 5 m
4.
Using 1st equation of motion braking motion:
Vf = Vi + at
where,
Vf = Final Speed = 0 m/s
Vi = Initial Speed = 10 m/s
a = acceleration = - 8m/s²
t = ?
Therefore,
0 m/s = 10 m/s + (-8m/s²)t
t = (10 m/s)/(8 m/s²)
t = 1.25 s
5.
Now, using second equation of motion:
Distance Covered While Braking = s₃ = Vi t + (1/2)at²
s₃ = (10 m/s)(1.25 s) + (1/2)(-8m/s²)(1.25 s)²
s₃ = 12.5 m - 5 m
s₃ = 7.5 m
6.
Total Distance = s = s₁ + s₂ + s₃
s = 80 m + 5m + 7.5 m
s = 92.5 m
What are the energy transfers in a torch?
Explanation:
The battery is a store of internal energy (shown as chemical energy). The energy is transferred through the wires to the lamp, which then transfers the energy to the surroundings as light. These are the useful energy transfers - we use electric lamps to light up our rooms.
A student connects AA batteries, that have a total voltage of 6.0 V, to light up a light bulb to create a series circuit. The circuit has a resistance of 50 Ω. How much current (A) flows through the circuit?
image
A.
0.03 A
B.
0.12 A
C.
75 A
D.
300 A
Answer:
0.12A
Explanation:
v=ir
I=v÷r
6÷50=0.12A
Which of the following describes one of Galileo Galilei's contributions to the development of the concept of gravity?
a.He conducted experiments with balls and inclined planes.
b.He theorized that Earth was at the center of the universe.
c.He theorized that planets move around the Sun in an elliptical pattern.
d.He calculated a value that is currently known as the gravitational constant.
Answer:
The correct option is;
c. He conducted experiments with balls and inclined planes
Explanation:
The inclined plane experiment conducted by Galileo Galilei was one of his most important experiments.
The experiment consisted of a grooved board with which a small metal ball is rolled down in, so as to analyze the held Aristotelian ideas about motion.
In the experiment, the focus was on acceleration, a concept that the previously held ideas about motion
A parachute provides an upward force of 400 N. If the person has a mass of 150.0 kg, what does the force due to gravity have to be in order for there to be a constant velocity in the down direction?
A) 1500.0 m/s/s
B) 400 N
C) 10 m/s/s
Answer:
1,500 N
Explanation:
Given:
Mass = 150 kg
Gravitational acceleration = 10m/s²
Find:
Force
Computation:
Force = mg
Force = 150 x 10
Force = 1,500 N
A sled slides down a snow-covered hill at constant speed. If the hillside is 10° above the horizontal, what is the coefficient of kinetic friction between the runners of the sled and the snow?
Answer:
The kinetic coefficient of friction between the runners of the sled and the snow is approximately 0.176.
Explanation:
At first we present a free body diagram of the sled as an image attached below. From 1st and 2nd Newton's Laws we know that an object is at equilibrium when it is either at rest or moving at constant velocity. The equations of equilibrium associated with the sled is:
[tex]\Sigma F_{x'} = f-W\cdot \sin \theta = 0[/tex] (1)
[tex]\Sigma F_{y'} = N-W\cdot \cos \theta = 0[/tex] (2)
Where:
[tex]\theta[/tex] - Inclination of the hillside, measured in sexagesimal degrees.
[tex]N[/tex] - Normal force from ground to sled, measured in newtons.
[tex]W[/tex] - Weight of the sled, measured in newtons.
[tex]f[/tex] - Kinetic friction between sled and ground, measured in newtons.
The definitions of kinetic friction and weight are, respectively:
[tex]f=\mu_{k}\cdot N[/tex] (3)
[tex]W = m\cdot g[/tex] (4)
Where:
[tex]\mu_{k}[/tex] - Kinetic coefficient of friction, dimensionless.
[tex]m[/tex] - Mass of the sled, measured in kilograms.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
By applying (3) and (4) in (1) and (2), we have the following system of equations:
[tex]\mu_{k}\cdot N-m\cdot g\cdot \sin \theta = 0[/tex] (1b)
[tex]N -m\cdot g \cdot \cos \theta = 0[/tex] (2b)
And by applying (1b) in (2b), we have the following expression for the kinetic coefficient of friction:
[tex]\mu_{k}\cdot m\cdot g \cdot \cos \theta -m\cdot g \cdot \sin \theta = 0[/tex]
[tex]\mu_{k} = \tan \theta[/tex] (5)
If we know that [tex]\theta = 10^{\circ}[/tex], then the kinetic coefficient of friction between the runners of the sled and the snow is:
[tex]\mu_{k} = \tan 10^{\circ}[/tex]
[tex]\mu_{k}\approx 0.176[/tex]
The kinetic coefficient of friction between the runners of the sled and the snow is approximately 0.176.
A man has a weight of 85 kg what is his weight
A. 833 N
B. 85 N
C. 724 N
D. 145 N
Answer:
A)833N
Explanation:
weight=9.8x85=833N
I hope it helps
PLEASE HELP , THOSE ARE ALL THE ANSWERS!
Answer:
I don't understand
Explanation:
Newton's third law of motion involves:
A) one force acting on one object
B) a force pair acting on two different objects
C) a force pair acting on one object
D) unbalanced forces acting on many objects
Answer:
B
Explanation:
There are a pair of forces acting on the 2 interacting objects
You're welcome <3
2. A go-cart travels once around a circular track with a radius of 200m. What is its
displacement?
A)200 m
B)1256.64 m
C)100 m
D)0 m
Answer:
ggggggg
Explanation:
who first calculated the value of G?
Answer:
Lord Henry Cavendish
Explanation:
The constant of proportionality in this equation is G - the universal gravitation constant. The value of G was not experimentally determined until nearly a century later (1798) by Lord Henry Cavendish using a torsion balance.
Answer: Lord Henry Cavendish.
Why do we wear rubber soled sneakers when we run? (PHYSICS)
Answer:
Rubber soled sneakers make it harder to slip while running
Explanation:
Una esfera de radio 0.4m tiene una masa de 300kg, se desea sumergir en agua para saber si flota o no. En este ejercicio use la densidad del agua en kg/m^3.
Answer:
La esfera no flotará pero se hundirá cuando se coloque en el agua porque su densidad es mayor que la del agua.
Explanation:
De la pregunta anterior, se obtuvieron los siguientes datos:
Radio (r) de la esfera = 0,4 m
Masa de esfera = 300 Kg
Densidad del agua = 1000 Kg / m³
A continuación, determinaremos el volumen de la esfera. Esto se puede obtener de la siguiente manera:
Radio (r) de la esfera = 0,4 m
Pi (π) = 3,14
Volumen (V) de la esfera =?
V = 4/3 πr³
V = 4/3 × 3,14 × 0,4³
V = 12,56 / 3 × 0,064
V = 0,27 m³
A continuación, determinaremos la densidad de la esfera. Esto se puede obtener como se ilustra a continuación:
Masa de esfera = 300 Kg
Volumen de esfera = 0,27 m³
Densidad de esfera =?
Densidad = masa / volumen
Densidad de la esfera = 300 / 0,27
Densidad de la esfera = 1111,11 Kg / m³
Comparando la densidad del agua y la de la esfera.
Sustancia >>>>>>> Densidad
Agua >>>>>>>>>>> 1000 Kg / m³
Esfera >>>>>>>>>> 1111,11 Kg / m³
De la ilustración anterior, podemos ver que la densidad de la esfera es mayor que la del agua.
Por lo tanto, la esfera no flotará sino que se hundirá cuando se coloque en el agua porque su densidad es mayor que la del agua.