for two vectors A and B, if A×B =6i+2j+5k, A.B=-13, A+B=-2i+j+2k and magnitude of vector A is 3. find the two vectors A anf B​

Answers

Answer 1

Two vectors are parallel when the angle between them is either 0° (the vectors point in the same direction) or 180° (the vectors point in opposite directions).

What is vectors ?

In both mathematics and physics, the term "vector" is used informally to describe certain quantities (also known as "scalars") that cannot be described by a single number or by the constituent parts of some vector spaces.

Historically, vectors were introduced in geometry and physics (usually in mechanics) for things like displacements, forces, and velocity that have both a magnitude and a direction. Similar to how lengths, masses, and time are represented by real numbers, these quantities can be thought of as geometric vectors.

Tuples, which are finite sequences of numbers with a definite length, are also referred to as vectors in some settings.

Tuples and geometric vectors may both be added to and scaled, and the idea of a vector space is a result of these vector operations.

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Related Questions

As a 3.0 kg bucket is being lowered into a 10 m deepwell, starting from top, the tension in the rope is 9.8 N. theacceleration of the bucket will be:____________A) 6.5 m/s2 downwardB) 9.8 m/s2 downwardC) zeroD) 3.3 m/s2 upwardE) 5.6 m/s2 upward

Answers

Answer:

A) 6.5 m/s²

Explanation:

Mass of the bucket, m = 3.0 kg

depth of the well, d = 10 m

tension on the rope, T = 9.8 N

The net downward force on the bucket is given as;

T = mg - ma

where;

a is downward acceleration of the bucket

9.8 = (3 x 9.8) - 3a

9.8 = 29.4 - 3a

3a = 29.4 - 9.8

3a = 19.6

a = 19.6 / 3

a = 6.53 m/s² downwards

Therefore, the acceleration of the bucket is 6.53 m/s² downwards

If a mass of an object is 20 kg on earth, so what will be its weight?

Answers

Answer:

200 Newton

Explanation:

Weight is the force with which earth pulls the object.

W = M× g

where m is mass and g is acceleration due to gravity whose value is approximately 10 Newton

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The subjective perception of the frequency of sound is called ?

Answers

Answer: The subjective perception of the frequency of sound is called a Pitch

Explanation: Because the Pitch has a lowest and highest  of a sound fundamental

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A car is stopped for a traffic signal. When the light turns green,
the car accelerates, increasing its speed from 0 to 5.20 m/s in
0.832 s. What are the magnitudes of (a) the linear impulse and
(b) the average total force experienced by a 70.0-kg passenger
in the car during the time the car accelerates?

Answers

Answer:

Impulse, p = 364 N·s
Force F =  437.5 N

Explanation:

First some definitions:

Momentum, p is defined as the product of the mass, m  and velocity v.
p = mv
Impulse, J is the change in momentum of a body
J = Δp = p₂ - p₁ = mv₂ - mv₁ = mΔv   where the subscript 1 refers to initial values and subscript 2 to final values.

Part (a)
Since the car is initially at rest, its initial momentum is 0.
When the car reaches a velocity of 5.20 m/s, the momentum experienced by a 70 kg passenger is

Δv = 5.20 - 0 = 5.20 m/s

p = 70 kg x 5.20 m/s =  50.3248 kg m/s =  364 N·s

p = 384 N.s

Part (b)

Force is given by F=m(Δv/Δt) = 70 kg x (5.20 m/s / 0.832 s) = 437.5 N
F = 437.5 N

Three people are trying to move a box. Which set of forces will result in a net
force on the box of 20 N to the right?
A.
B.
O C.
O D.
18 N
55 N
55 N
6 N
← PREVIOUS
1₂
28 N
16 N 17 N
0
10 N
17 N
$
16 N
-
20 N
6 N



Correct answer is A

Answers

Answer:

A

Explanation:

18-28=10

10+10=20

20N to the right

A toy car in the figure below runs off the edge of a table that is h = 1.36 m high. The
car lands d= 0.88 m from the base of the table. How fast was the car going on the
table?

Answers

The toy car was going at a speed of 1.66 m/s on the table.

When the toy car runs off the edge of the table, it travels vertically as well as horizontally and it is an example of a horizontal projectile from a height.

The distance covered vertically will be equal to the height of the table which is 1.36m. And horizontal distance is given as d.

Vertical distance = H = 1.36m

Horizontal distance = d = 0.88m

Now, we for a free-falling body, in

Speed in vertical direction = u  = 0 m/s

Distance = h = 1.36

Using the second equation of motion,

h = ut + 1/2gt²

Put in the value, we get

1.36 = (0)t + 1/2(9.8)t²

t² = 1.36/4.9

t² = 0.278

t = 0.53 seconds

Now distance traveled in a horizontal direction is given by

Distance in horizontal direction = Speed on table × time of travel

Put in the value, we get

0.88 = V × 0.53

V = 0.88/0.53

V = 1.66 m/s

So, the toy car was going at a speed of 1.66 m/s on the table.

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What is the voltage of a circuit that has a current of 3.7 amps and a resistance of 1.5 ohms.

Answers

Answer:

V = 5.55 volts

Explanation:

Given that,

Current, I = 3.7 A

Resistance, R = 1.5 ohms

We need to find the voltage of the circuit. Let V is the voltage. We can find it using Ohm's law as follows :

V = IR

Substituting all the values, we get :

[tex]V=3.7\times 1.5\\\\=5.55\ V[/tex]

So, the voltage of the circuit is 5.55 V,

Suppose, that you are measuring the length of a wood block and the edge of your block appears to be lined up exactly with a millimeter mark. How would you express the estimate part of a millimeter when you record the block’s length?

Answers

When taking the measurement, the estimate part of a millimeter when recording the block’s length can be expressed as ± 0.5 mm.

What are measurements?

Measurements are the processes by which the attributes and properties of a given object or substance is quantified.

There are two types of measurements that can be obtained from any given object and they are:

quantitative measurementsqualitative measurements

Quantitative measurements measures the properties of objects in terms of numbers. Some examples of quantitative measurements are length, temperature, time, mass, etc.

Qualitative measurements describe the non-numerical features of objects such as color, texture, etc.

The measurement of length of a block of wood is a quantitative measurement.

The uncertainty or estimate of a measurement is half plus or minus the smallest division in the measurement.

The uncertainty or estimate of the millimeter block = ¹/₂ * 1 mm

The uncertainty or estimate of the millimeter block = ±0.5 mm

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Dale and Alex push on opposite sides of a couch. Dale pushes to the left with a force of 40 N, while Alex pushes to the right with a force of 32 N. If the
couch has a mass of 28 kg, what is the acceleration of the couch?
A. 2.6 m/s^2 right
B. 2.6 m/s^2 left
C. 0.3 m/s^2 left
D. 0.3 m/s^2 right

Answers

0.3 m/s^2 left will be  the acceleration of the couch.

we have given in the statement

force towards left  40 N

force towards right 32 N

net force = 40-32 = 8 N towards left

couch  mass = 28 kg

now we will use newtons 2nd law to find acceleration

F=ma, here f is force m is mass a is acceleration

a=F/m

a=8/24

a=0.285 ≅ 0.3 N

An object's rise in velocity rate is referred to as acceleration. It is a vector quantity that is sign-sensitive, and the route shift and body speed variance establish the sign norm. it's unit is m/s^2

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0.3 m/s squared left Answer:

Explanation:

PLEASE HELP ME!! I NEED ANSWERS ASAP!!!!

Answers

Answer:

I do not know the answer because not all of the information is there.

Explanation:

Answer:

Beep Beep

Explanation:

Which of the following will increase if the voltage in a circuit is increased?
Check all that apply
A.Magnetic force
B. Resistance
C. Current
D. Heat produced by the circuit

Answers

Answer:

D i think (apologies if incorrect)

F x T = m (Vf - Vi)
in this equation what does the M stand for

Answers

Answer:

m = mass [kg]

Explanation:

This equation is characteristic of the amount of motion and momentum.

[tex]F*t = m*(v_{f}-v_{i})[/tex]

where:

F = force [N] (units of Newtons)

t = time = [s]

m = mass [kg]

Vf = final velocity [m/s]

Vi = initial velocity [m/s]

Now using the units and placing them in the equation above.

[tex][N]*[s] = [kg]*(m/s-m/s)\\[/tex]

[tex][N]=[kg*m/s^{2} ][/tex]

Now replacing:

[tex][kg*m/s^{2}]*[s]=[kg*m/s][/tex]

The s² is cancelled with the s, therefore.

[tex][kg*m/s]=[kg*m/s][/tex]

A source of heat at 1000 K transfers 1000 kW of power to a power generation device, while producing 400 kW of useful work. Determine the second law efficiency of the system, if the environment is at 300 K.

Answers

Answer:

The value is [tex]\eta _2 = 0.57[/tex]

Explanation:

From the question we are told that

    The temperature of the heat source is [tex]T_s = 1000 \ K[/tex]

    The amount of power transferred is  [tex]P_s = 1000 \ kW = 1000 *10^{3} \ W[/tex]

      The work produced is  [tex]W = 400 \ kW[/tex]

       The temperature of the environment [tex]T_e = 300 \ K[/tex]

Gnerally the Carnot efficiency of the system is mathematically represented as

        [tex]\eta_c = 1 -\frac{T_e}{T_s}[/tex]

=>    [tex]\eta_c = 1 -\frac{300}{1000}[/tex]

=>      [tex]\eta_c = 0.7[/tex]

Generally the first  law efficiency of the system is mathematically represented as

            [tex]\eta _1 = \frac{W}{P_s}[/tex]

=>         [tex]\eta _1 = \frac{400}{1000}[/tex]  

=>         [tex]\eta _1 = 0.40[/tex]

Generally the second  law efficiency of the system is mathematically represented as

                [tex]\eta _2 = \frac{\eta_1}{\eta_c}[/tex]

=>               [tex]\eta _2 = \frac{0.4}{0.7}[/tex]

=>               [tex]\eta _2 = 0.57[/tex]

As a ladder leans against a wall it exerts a force on both the wall and ground. What are the two reactant forces on the ladder?
Responses

−Fwall on ladder and −Fground on ladder
−Fwall on ladder and −Fground on ladder
upper F subscript ball on bat baseline equals negative upper F subscript bat on ball baseline

Fwall on ladder and −Fground on ladder
Fwall on ladder and −Fground on ladder
upper F subscript ball on bat baseline equals negative upper F subscript bat on ball baseline

Fwall on ladder and Fground on ladder
Fwall on ladder and Fground on ladder
upper F subscript ball on bat baseline equals negative upper F subscript bat on ball baseline

−Fwall on ladder and Fground on ladder
−Fwall on ladder and Fground on ladder

Its -Fwallonladdy and -fgroundonladder just made sure to add this since no one else did yet

Answers

The two reactant forces on the ladder are -Fwall on Ladder and -Fground on Ladder

What are the two reactant forces on the ladder?

To know the reactant forces on the ladder, we use Newton's third law of motion.

What is Newton's third law of motion?

Newton's third law of motion states that for every action, there is an equal and opposite reaction.

So, for the ladder, as the ladder leans against a wall it exerts a force on both the wall and ground.

Now, since the ladder exerts a force on the wall, according to Newton's third law, the ground also exerts an equal but opposite force on it. If the force of the ladder on the wall is Fladder on wall, then the reaction force of wall on the ladder is Fwall on ladder.

So, Fladder on wall = -Fwall on Ladder

Also, since the ladder exerts a force on the ground, according to Newton's third law, the ground also exerts an equal but opposite force on it. If the force of the ladder on the ground is Fladder on ground, then the reaction force of ground on the ladder is Fground on ladder.

So, Fladder on ground = -Fground on Ladder

So, the two reactant forces on the ladder are -Fwall on Ladder and -Fground on Ladder

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A person holds a ladder horizontally at its center. Treating the ladder as a uniform rod of length 4.15 m and mass 7.98 kg, find the torque the person must exert on the ladder to give it an angular acceleration of 0.396 rad/s2.

Answers

Answer:

4.535 N.m

Explanation:

To solve this question, we're going to use the formula for moment of inertia

I = mL²/12

Where

I = moment of inertia

m = mass of the ladder, 7.98 kg

L = length of the ladder, 4.15 m

On solving we have

I = 7.98 * (4.15)² / 12

I = (7.98 * 17.2225) / 12

I = 137.44 / 12

I = 11.45 kg·m²

That is the moment of inertia about the center.

Using this moment of inertia, we multiply it by the angular acceleration to get the needed torque. So that

τ = 11.453 kg·m² * 0.395 rad/s²

τ = 4.535 N·m

The Torque will be "4.535 N.m".

Given:

Mass of ladder,

m = 7.98 kg  

Length of ladder,

L = 4.15 m

The moment of inertia will be:

→ [tex]I = \frac{mL^2}{12}[/tex]

     [tex]= \frac{7.98\times (4.15)^2}{12}[/tex]

     [tex]= \frac{7.98\times 17.2225}{12}[/tex]

     [tex]= 11.45 \ kg.m^2[/tex]

hence,

The torque will be:

→ [tex]\tau = 11.453\times 0.395[/tex]

      [tex]= 4.535 \ N/m[/tex]

Thus the above approach is correct.      

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if A.B=A.C
does this imply that B must be equal to c ?
I need answer with example please ​

Answers

Answer:

Yes

Explanation:

[tex]Consider\ three\ variables\ a,b\ and\ c.\\If,\\ab=ac\\a*b=a*c\\We\ may\ now\ divide\ the\ LHS\ and\ RHS\ by\ a,\\Hence,\\\frac{a*b}{a} =\frac{a*c}{a}\\Hence,\\b=c[/tex]

[tex]Ex: \\Consider\ a=5, b=6.\\Hence\ if,\\a*b=a*c\\5*6=5*c\\Hence,\\30=5c\\Hence, c=\frac{30}{5}\\c=6\\As\ b\ also\ equals\ to\ 6,\\b=c[/tex]

PLZZZ I will give brainliest. A ball that contains mechanical energy is rolled across the floor. You notice the ball is slowing down. If the ball started with 20 units of energy, explain how much energy would there be when the ball comes to a complete stop? How can you tell?

Answers

Answer: because of friction it will stop rolling completly

Explanation:

7. What is the acceleration of a 24.00 kg mass pushed by an 8.0 N force?

Answers

Answer:

3 m/s²

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

f is the force

m is the mass

From the question we have

[tex]a = \frac{24}{8} \\ [/tex]

We have the final answer as

3 m/s²

Hope this helps you

10. The Earth's radius is about 6370 km. An object that has a mass of 20 kg is taken to a
height of 160 km above the Earth's surface. How much does the object weigh at this
height?

Answers

Answer:

Weight:

P =m·g₁ = 20·9.55 = 191 H

Explanation:

Given:

R = 6 370 км = 6 370·10³ m

m = 20 kg

h = 160 km = 160·10³ m

g = 9.8 m/s²

____________________

P - ?

Acceleration of free fall at the Earth's surface:

g = G*M / R²    (1)

Acceleration of free fall at height h:

g₁ = G*M / (R + h) ²    (2)

Divide (1) by (2):

g / g₁ = ((R + h) / R)²

g / g₁ = ( 1 + h / R)² = ( 1 + 160 / 6 370)² ≈ 1.026

g₁ = g / 1.026 = 9.8 / 1.026 ≈ 9.55 m/s²

Weight:

P =m·g₁ = 20·9.55 = 191 H

A powerful missile reaches a speed of 5 kilometers per second in 10 seconds after its launch. What is the average acceleration of the missile during this period?

A. 0.2 meters/second2
B. 0.4 centimeters/second2
C. 0.5 meters/second2
D. 0.5 kilometers/second2

Answers

Answer:

D option

Explanation:

please mark me brainliest and 5 star

Answer:

D. 0.5 km/s2

Explanation:

Damage to internal organs will present as pain associated with a particular surface area of the body. Why would something like irritation to the diaphragm, which is between the thoracic and abdominal cavities, feel like pain in the shoulder or neck?

Answers

A dish shaped large muscle which moves up and down when there is contraction and expansion of lungs is the diaphragm which is present between the chest cavity and lower abdominal region. The action of the diaphragm is affected by an inflammation occurring below the muscular disc which will affect the process of breathing. The forceful breathing may result in strain and stress in the back muscles of the human body. This in turn causes pain in the shoulder.

The time taken by a mass projected vertically
upwards to reach the maximum height (with air
resistance not neglected) is 10 sec. The time of
descent of the mass from the same height will be​

Answers

Answer:

10s

Explanation:

The time to get to the maximum would be the same as the time to get down to the maximum unless somehow gravity’s changes during the duration it goes up to and from maximum height.

At the mail racing championship in England, the winner moved at an average velocity of 2.4 mm/s [ford] for 140 s. Determine the winning snail's displacement during this time interval. [​

Answers

Answer:

Explanation: 1.2 mm

Time= 140 sec

Initial Velocity= 0

Average Velocity= 2.4 mm/s

Displacement=  0.5* (2.4/140) *140 = 1.2 mm

How much work is done by an applied force to lift a 15-Newton 3Meters and 9.8?

Given=
Unknown=
Formula=
Solution=
Answer=​

Answers

The work done by the applied force of 15 Newton to lift the object up 3 meters is 45 J

W = F d

W = Work done

F = Force

d = Distance

F = 15 N

d= 3 m

W = 15 * 3

W = 15 J

Work done is the amount of force required to move an object. It is denoted by W. Its unit is usually Joules.

Therefore, the work done to lift the object is 15 J

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HELP right awayyy !!!

Answers

Answer:

Question 4 is actually Acceleration

4 is actually acceleration

The two ends of an iron rod are maintained at different temperatures. The amount of heat that flows through the rod by conducting DOES NOT depend on

Answers

Answer:

D mass of the iron rod

Explanation:

A) the length of the iron rod.

B) the thermal conductivity of iron.

C) the temperature difference between the ends of the rod.

D) the mass of the iron rod.

E) the duration of the time interval

The amount of heat that will flow through an iron rod whose two ends are maintained at different temperatures would depend on the thermal conductivity of the iron, the temperature difference between the two ends, the length of the iron rod, and the duration of flow of heat.

The thermal conductivity of any material is an indication of the ability of the materials to conduct heat. The higher the thermal conductivity, the higher the amount of heat a material can conduct within a specified period. Hence, the amount of heat that will flow through the iron rod depends on its thermal conductivity.

The temperature difference between two solid materials depends on the amount of heat that will flow across the materials by conduction. The higher the difference, the more the amount of heat that will flow. Hence, the amount of heat that would be conducted depends on the temperature difference between the two ends of the iron rod

The amount of heat that would move my conduction also depends on the distance that would be traveled by the heat. Due to heat loss to the surrounding, the shorter the distance, the more the heat and vice versa. Hence, the amount of heat that will flow through an iron rod depends on the length of the iron rod.

The duration of flow also dictates the amount of heat that will flow between two regions by conduction. The more the duration, the more the heat, provided that other conditions remain constant.

The only option that the amount of heat that would be conducted does not depend on is the mass of the iron rod.

The correct option is D.

A 120V AC signal is available at the wall port. You are required to convert it to a constant DC voltage of 12V for a laptop to operate. What are the three electrical components you will be using to achieve the same? Name the components in order and the function it performs.

Answers

Answer:

The following components shall be used in given order:

1. Step Down Transformer     2. Diode as Rectifier     3. Capacitor

Explanation:

The following components shall be used in given order:

1. Step Down Transformer     2. Diode as Rectifier     3. Capacitor

1.STEP DOWN TRANSFORMER:

The step down transformer is first used to convert the 120 V AC signal into 12 V AC signal. Because the output required is of 12 V.

2.DIODE AS RECTIFIER:

Now, the PN Junction diode is used as a rectifier to convert the 12 V AC signal to 12 V  DC signal.

3.CAPACITOR:

Now, the output is in waveforms. So, in order to linearize it in the form of DC current, we use capacitor. The main function of capacitor is to smoothen the signal into a straight line.

Helium balloons pop in a hot car because

Answers

Answer:

This is because helium molecules get bigger when they heat up , so if your balloons keep getting hotter , they will eventually pop

Answer:

the helium molecules within the ballon expand as they heat up, resulting in the eventually resulting in popping.

Explanation:

^^^^^

In winter morning, as soon as we wake the air inside the room is cold but if up, the out and return to the same room, we we goo feel warm, why?​

Answers

Answer:

it is all because of nature

The world record for a woman running a marathon is approximately 2.25 hours. If a marathon's distance is 26.2 miles (42164.81 meters) and it is run
in a southeast direction, what is the velocity?
60 mph southeast
0.09 mph southeast
Omph southeast
11.6 mph southeast

Answers

Answer:

11.6mph South East

Explanation:

Given parameters:

Time = 2.25hrs

Displacement  = 26.2miles south east

Unknown:

Velocity = ?

Solution:

Velocity is the displacement divided by the time taken. It is a vector quantity with both magnitude and direction.

 Now;

       Velocity  = [tex]\frac{displacement}{time taken}[/tex]

       Velocity  = [tex]\frac{26.2}{2.25}[/tex]   = 11.6mph South East

Answer:

11.6mph south east.

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