2. (a). Three forces that act on a particle are given by F1 = (20 i – 36 j + 73 k) N, F2 = (-17 i

+ 21 j – 46 k) N, and F3 = (-12 k) N. Find their resultant vector. Also find the magnitude

of the resultant to two significant figures.

(b). A vector has an x- component of -25.0 units and a y- component of 40.0 units. Find

the magnitude and direction of the vector.​

Answers

Answer 1
F3 -4 wouldn’t even be a guhd add up tbsh jus delete it

Related Questions

When you eat food, not all of the food can be broken down into the basic building blocks and why?

Answers

Answer:

cause you crazy..

Explanation:

A 50 kg girl in a roller coaster with a speed of 30 m/s is traveling around a horizontal circle with a radius of 25 m. What is the centripetal force acting on the girl.

Answers

Answer:

F=mv^2/r = 50x(900)/625 = 72N

The centripetal force of 180 N is acting on the girl who is in the roller coaster ride with a speed of 30 m/s in a horizontal circle with a radius of 25m.

What is Centripetal force?

A centripetal force is the force which makes a body follow a circular path. Here, the direction is always orthogonal to the motion of body and towards a fixed point of instantaneous center of curvature of path.

The centripetal force acting on an object in circular path can be calculated with the help of a formula:

F = mv²/r

where, F = centripetal force acting on the object,

m = mass of the object,

v = velocity of the object,

r = radius of the circular path.

By putting the given values into the formula, we get:

F = [50 × (30)²]/25

F = [50 × 900]/25

F = 4500/25

F = 180 N

Therefore, the centripetal force acting on the girl is 180 N.

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kid is bouncing on a pogo stick. he oscillates 22.0 times in 14.9 s. What is his period?

Answers

Answer:

Period = 0.68 seconds

Explanation:

Given the following data;

Number of oscillation = 22

Time = 14.9 seconds

To find the period;

Method I.

Period = time/number of oscillation

Period = 14.9/22

Period = 0.68 seconds.

Method II.

We would find the frequency of the wave;

Frequency = time/number of oscillation

Frequency = 22/14.9

Frequency = 1.48 Hertz

Next, we find the period;

Period = 1/frequency

Period = 1/1.48

Period = 0.68 seconds


What is the power of a stereo that has an intensity of 3.5X105 W/m2 at a distance of 12.4 m

Answers

Enehejeejejskslalsjbdbdjddjdududbdbdnd

Can you somebody answer this question for me please?

Answers

A is the correct answer

Answer:

The answer is B - the bending of rock layers happens due to stress, and this process is called folding. Faults are when it looks broken/displaced

Which statement describes the redox reaction involved in photosynthesis?
A. It transfers energy to ATP molecules so energy can be transferred.
B. It is a combustion reaction in which energy is released.
C. CO2 is removed from the atmosphere, and O2 is released
D. O2 is removed from the atmosphere, and CO2 is released​

Answers

The statement 'CO2 is removed from the atmosphere, and O2 is released' describes the redox reaction involved in photosynthesis. It is a redox reaction.

What is photosynthesis?

Photosynthesis refers to a series of reactions by which plants can produce simple carbohydrates by using solar radiation and oxygen (O2).

These photosynthetic reactions are well known to release carbon dioxide (CO2) into the atmosphere.

During Photosynthesis, CO2 is reduced to simple carbohydrates (e.g., glucose), while water (H2O) is oxidized to O2, thereby producing a redox reaction.

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Which of the following correctly defines the speed of a wave?
O A. v=1
B. A = vf
O C. v= f 2
OD. =v2

Answers

The correct answer is B I think

Answer:

V = f x λ

Explanation:

The options are confusing

a container of mass 200kg contains 160cm
of liquid. The total mass of the container and liquid is 520g. what is the density of the liquid?​

Answers

Answer:

mass of liquid = total mass - mass of container

m = 52000kg - 200kg

m = 519800

D = m/v

D = 519800/160

D = 3,248.75 kgm-³

Please help me if you can.
I can't figure out how the answer for number 30 is C and 31 is C. My question is how did they get that answer?

Answers

Answer:

30. $3.85

31. $2.22

Explanation:

30. The time duration of the kitchen clock is left on = All day = 24 hours

The power rating of the kitchen clock, P = 4 watts

The electricity cost in Alberta, R = $0.11 per kilowatt hour

The total number of hours the kitchen clock is on during the year, 't', is given as follows;

t = Number of hours per day × Number of days per year

∴ t = 24 hours/day × 365 days/year = 8,760 hours

The energy consumption of the kitchen clock, per year, E = P × t

∴ E = 4 watts × 8,760 hours = 35,040 watts-hour = 35.040 kw·h

The cost of operating the clock in one year, C = E × R

∴ Operating cost for the kitchen clock

∴ C = 35.040 kw·h × $0.11/(kw·h) = $3.8544 ≈ $3.85

The cost of operating the clock in one year, C ≈ $3.85

31. The power rating of the ghetto blaster, P = 28 watts

The time duration the ghetto blaster was on during an average month = All day = 24 hours

The number of days during an average month, n = 30 days

The cost of electricity in Alberta, R = $0.11 per kilowatt hour

The time in hours the ghetto blaster was on, t = 30 days/month × 24 hours/day

∴ t = 720 hours per month

The cost of operating the ghetto blaster in one month, C = P × t × R

∴ C = 28 W × 720 hours × 1 kw·h/(1000 w·h)× $0.11/(kw·h) = $2.2176

∴ The cost of operating the ghetto blaster in one month, C ≈ $2.22

A transverse wave vibrates its medium __________ to the forward motion of the wave, and a longitudinal wave vibrates its medium __________ to the forward motion of the wave.

perpendicular; circularly

parallel; circularly

parallel; perpendicular

perpendicular; parallel

Answers

Answer:

Perpendicular ; Parallel

is an object that has 3 electrons and 5 protons a positive charge?

Answers

Answer:

Hello, Yes i believe it would be a positive charge considering electrons have a negative charge while protons have a positive charge.

Explanation:

define transition element​

Answers

Answer:

Explanation:

In chemistry, the term transition metal has three possible definitions: The IUPAC definition defines a transition metal as "an element whose atom has a partially filled d sub-shell, or which can give rise to cations with an incomplete d sub-shell".

Answer:

Transition elements (also known as transition metals)

Explanation:

are elements that have partially filled d orbitals. IUPAC defines transition elements as an element having a d subshell that is partially filled with electrons, or an element that has the ability to form stable cations with an incompletely filled d orbital.

How many people does it take to change a lightbulb?

Answers

A lightbulb joke is a joke cycle that asks how many people of a certain group are needed to change, replace, or screw in a light bulb. Generally, the punch line answer highlights a stereotype of the target group. There are numerous versions of the lightbulb joke satirizing a wide range of cultures, beliefs and occupations.

PLEASE HELP ME I AM TIMED!

Answers

Answer: B

Explanation: I can tell the block weights more since the water went down

Initial velocity vector vA has a magnitude of 3.00 meters per second and points 20.0o north of east, while final velocity vector vB has a magnitude of 6.00 meters per second and points 40.0o south of east. Find the magnitude and the direction of the change in velocity vector Δv (which is the vector subtraction of the two vectors: final velocity vector minus initial velocity vector).

Answers

Answer:

[tex]5.2\ \text{m/s}[/tex]

[tex]70^{\circ}[/tex] south of east

Explanation:

[tex]v_a[/tex] = 3 m/s

[tex]\theta_a[/tex] = [tex]20^{\circ}[/tex] north of east

[tex]v_b[/tex] = 6 m/s

[tex]\theta_b[/tex] = [tex]40^{\circ}[/tex] south of east = [tex]360-40=320^{\circ}[/tex] north of east

x and y component of [tex]v_a[/tex]

[tex]v_{ax}=v_a\cos \theta\\\Rightarrow v_{ax}=3\times \cos 20^{\circ}\\\Rightarrow v_{ax}=2.82\ \text{m/s}[/tex]

[tex]v_{ay}=v_a\sin\theta\\\Rightarrow v_{ay}=3\times \sin20^{\circ}\\\Rightarrow v_{ay}=1.03\ \text{m/s}[/tex]

x and y component of [tex]v_b[/tex]

[tex]v_{bx}=v_b\cos \theta\\\Rightarrow v_{bx}=6\times \cos 320^{\circ}\\\Rightarrow v_{bx}=4.6\ \text{m/s}[/tex]

[tex]v_{by}=v_b\sin\theta\\\Rightarrow v_{by}=6\times \sin320^{\circ}\\\Rightarrow v_{by}=-3.86\ \text{m/s}[/tex]

[tex]\Delta v=v_b-v_a\\\Rightarrow \Delta v=(4.6-2.82)\hat{i}+(-3.86-1.03)\hat{j}\\\Rightarrow \Delta v=1.78\hat[i}-4.89\hat{j}[/tex]

Magnitude

[tex]|\Delta v|=\sqrt{(-4.89)^2+1.78^2}\\\Rightarrow \Delta v=5.2\ \text{m/s}[/tex]

Direction

[tex]\theta=\tan{-1}|\dfrac{-4.89}{1.78}|\\\Rightarrow \theta=70^{\circ}[/tex]

The magnitude of the change in velocity vector is [tex]5.2\ \text{m/s}[/tex] and the direction is [tex]70^{\circ}[/tex] south of east.

The change in velocity will be  [tex]\Delta V=5.2\ \frac{m}{s}[/tex] and the direction will be [tex]70^o[/tex] South to east.

What are vector quantities?

Any quantity which is defined by its magnitude and direction both are called as the vector quantities.

Now the data given in the question will be given as:

[tex]V_a[/tex] = 3 m/s

[tex]\theta[/tex] = [tex]20^o[/tex] north of east

[tex]V_b[/tex] = 6 m/s

[tex]\theta[/tex] =  [tex]40^o[/tex]south of east =  360-40=320 north of east

Now we will find the x and y component of [tex]V_a[/tex]

[tex]V_{ax}=V_acos\theta[/tex]

[tex]V_{ax}=3\times Cos20[/tex]

[tex]V_{ax}=2.82\ \frac{m}{s}[/tex]

[tex]V_{ay}=V_aSin\theta[/tex]

[tex]V_{ay}=3\times Sin20[/tex]

[tex]V_{ay}=1.03\ \frac{m}{s}[/tex]

Now we will find the x and y component of [tex]V_b[/tex]

[tex]V_{bx}=V_bcos\theta[/tex]

[tex]V_{bx}=6\times cos\320[/tex]

[tex]V_{bx}=4.6\ \frac{m}{s}[/tex]

[tex]V_{by}=V_bSin\theta[/tex]

[tex]V_{by}=6\times Sin320[/tex]

[tex]V_{by}=-3.86\ \frac{m}{s}[/tex]

Now change in velocity will be

[tex]\Delta V=V_b-V_a[/tex]

[tex]\Delta V=(4.6-2.82)i+(-3.86-1.03)j[/tex]

[tex]\Delta V=1.78i-4.89j[/tex]

The magnitude can be find out as follows:

[tex]\Delta V=\sqrt{(-4.89^2+(1.78^2)}[/tex]

[tex]\Delta V=5.2\ \frac{m}{s}[/tex]

The direction of the vector will be

[tex]\theta= tan^{-1}(\dfrac{-4.89}{1.78})[/tex]

[tex]\theta=70^o[/tex]

Thus the change in velocity will be  [tex]\Delta V=5.2\ \frac{m}{s}[/tex] and the direction will be [tex]70^o[/tex] South to east.

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What must be true about a surface in order for diffuse reflection to occur?

Answers

Answer:

carpet

Explanation:

Diffuse reflection is the reflection of light from a surface such that an incident ray is reflected at many angles rather than at just one angle as in the case of specular reflection.

The structure of carpet's surface is as shown. Thus it shows large amount of diffuse reflection.

A longitudinal wave is observed. Exactly 6 crests are observed
to move past a given point in 9.1 s. Its wavelength is 2.4 m and
its frequency is 0.66 HZ. What is the speed of the wave?

Answers

The speed of the wave is 1.58 meters per second (or 1.584 if you don’t round it).
You multiply wavelength by frequency to get the speed of a wave.
2.4 times 0.66 = 1.548 meters per second.

If you didn’t have the frequency before hand, you would just divide the 6 crests by the 9.1 seconds.

Which of the following is an example of improving communication skills?

Answers

The question is incomplete as it does not provide options to choose from or any context. instead of this, I will explain how to improve communication skills. improving communication skills takes practice, self-awareness, and a willingness to learn and grow. By focusing on these key areas, you can improve your ability to communicate effectively with others in a variety of settings.

What is communication skill?

Communication skills refer to the ability to convey information effectively and efficiently to others, both verbally and non-verbally. Effective communication involves active listening, clarity of expression, and an understanding of the message being conveyed.

There are several ways to improve communication skills, including:

Practice: Communication skills can be improved through regular practice. Look for opportunities to communicate with others, and take the time to reflect on your communication style and how you can improve.

Active listening: Effective communication requires active listening skills. Pay attention to what others are saying and ask questions to clarify your understanding.

Nonverbal communication: Nonverbal cues such as body language, eye contact, and facial expressions can convey important messages. Practice being aware of and controlling your own nonverbal cues to enhance your communication skills.

Clarity of expression: Clearly expressing your ideas and thoughts is essential for effective communication. Practice organizing your thoughts and speaking clearly and concisely.

Empathy: Being able to put yourself in someone else's shoes and understand their perspective is an essential communication skill. Practice showing empathy by actively listening and acknowledging the other person's feelings.

Feedback: Seek feedback from others on your communication skills. This can help you identify areas for improvement and refine your communication style.

Therefore, It takes time, effort, self-awareness, and a commitment to learn and develop new abilities to improve communication. You can enhance your capacity to interact successfully with others in a range of circumstances by concentrating on five important areas.

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Where does the pendulum have 100 J of potential energy?

Answers

Answer:

Potential energy is related to mass and height. More context is required otherwise the answer here is an equation with several unknowns. PE = mgL(1 – COS θ) where θ is the angle away from the vertical and L is the length of the string.

Explanation:

Water is flowing at 4.0 m/s in a circular pipe. If the diameter of the pipe decreases to 1/2 of its former value, what is the velocity of the water?

Answers

Answer:

v₂ = 16 m/s

Explanation:

We can use the continuity equation, which is as follows:

[tex]A_1v_1 = A_2v_2\\[/tex]

where,

A₁ = Area of inlet = πd²/4

A₂ = Area of outlet = π(d/2)²/4 = πd²/16

v₁ = velocity at inlet = 4 m/s

v₂ = velocity at outlet = ?

Therefore,

[tex](\frac{\pi d^2}{4})(4\ m/s)=(\frac{\pi d^2}{16})v_2\\\\[/tex]

v₂ = 16 m/s

Explain how it is that you could have 2 parents with brown eyes, but you have blue eyes. Talk about the role chromosomes, genotypes, and alleles play in making something like that happen.

Help please will give b to the best one!

Answers

Answer:

Because the two genes depend on each other, it is possible for someone to actually be a carrier of a dominant trait like brown eyes.  And if two blue eyed parents are carriers, then they can have a brown eyed child.  Genetics is much bkj

Explanation:

So all you light eyed parents with dark eyed kids, stop asking those paternity questions (unless you have other reasons to be suspicious).  Darker eyed kids are a real possibility that can now be explained with real genes.  

As an airplane takes off, the air flows across the wings of the airplane. Which of the following would be the best description? I. The air flow across the top of the wing is greater than the air flows across the bottom of the wing. II. The air flow across the top and bottom of the wing is the same. III. The lift force is present because the pressure across the top is less than the pressure across the bottom of the wing.

Answers

Answer:

III. The lift force is present because the pressure across the top is less than the pressure across the bottom of the wing.

Explanation:

2. Why do you fall forward when you stub your toe on a chair? Explain in terms (meaning use
the words in the law in your answer) of inertia and Newton's llaw.
STUBBED
MY TOES
3. Why do you fly forward when hitting a curb while riding a skateboard or bike? Explain in
terms of inertia and Newton's 1" law.
4. Come up with your own example of Newton's first lawl Again explain using inertia and
Newton's l1st law

Answers

Answer:

because u feel pain and u get shaky and fall

Explanation:

Answer:

Explanation:because it hurts so you fall

1:How are energy and amplitude of a wave related
2:Define Wavelength
3:What unit is the frequency of a wave measured in?

Please help this is due in 25 minutes

Answers

Answer:

2

Explanation:

wave length is the distance between corresponding points of two consecutive waves

3. hertz


Q3. If each tape represents the distance travelled by the object for 1
second, then what 'quantity' does each piece of tape provide?​

Answers

No clue brother this one diff kit

The base of a box is .45 m by .65 m. It weighs 8694 N. What is the pressure exerted on the floor by the box?

Answers

Answer:

[tex]Pressure = 29723.1\ N/m^2[/tex]

Explanation:

Given

[tex]Force = 8694N[/tex]

[tex]Length = 0.45m[/tex]

[tex]Width = 0.65m[/tex]

Required

The force exerted on the floor by the box

First, calculate the area covered by the box (i.e. the base area)

[tex]Base\ Area = Length * Width[/tex]

[tex]Base\ Area = 0.45m * 0.65m[/tex]

[tex]Base\ Area = 0.2925m^2[/tex]

Pressure is calculated as:

[tex]Pressure = \frac{Force}{Area}[/tex]

[tex]Pressure = \frac{8694N}{0.2925m^2}[/tex]

[tex]Pressure = 29723.0769231\ N/m^2[/tex]

[tex]Pressure = 29723.1\ N/m^2[/tex] --- approximated

A contour map has 14 concentric circles, each placed 1/2 centimeters apart. The map's scale indicates 1cm = 10 ft. What is the structure, and what are its dimensions?

Answers

Answer:

B. A hill 70ft tall.

Explanation:

The drawing shows a horizontal ray of white light incident perpendicularly on the vertical face of a prism made of crown glass. The ray enters the prism, and part of the light undergoes refraction at the slanted face and emerges into the surrounding material. The rest of the light is totally internally reflected and exits through the horizontal base of the prism. The colors of light that emerge from the slanted face of the prism may be chosen by altering the index of refraction of the material surrounding the prism. Find the required index of refraction of the surrounding material so that (a) only red light and (b) all colors except violet emerge from the slanted face of the prism. Take n

Answers

Answer:

The answer is "1.0748 and 1.0875".

Explanation:

Please find the complete question in the attachment file.

The incidence angle is [tex]i=45^{\circ}[/tex] for all colors When the angle is r, then use [tex]\frac{\sin{i}}{\sin{r}}=\frac{n_{o}}{n}[/tex] . Snell's rule Where [tex]n_{o}[/tex] is an outside material reflectance (same hue index) or n seems to be the crown glass index of the refraction, That index of inclination is [tex]90^{\circ}[/tex] as the light in color shifted behaver from complete inner diffraction to diffraction.

Whenever the external channel has a thermal conductivity for the red light, that's also

[tex]n_{o}=\frac{n_{r}\sin{45^{\circ}}}{\sin{90^{\circ}}}=\frac{1.520\times\sin{45^{\circ}}}{\sin{90^{\circ}}}=1.0748[/tex]

When outside the material has a refractive index, this happens with violet light.

[tex]n_{o}=\frac{n_{r}\sin{45^{\circ}}}{\sin{90^{\circ}}}=\frac{1.538\times\sin{45^{\circ}}}{\sin{90^{\circ}}}=1.0875[/tex]

In point a, The only red light flows out from the leaned face and the residual colors are mirrored mostly on prism for the primary benefits [tex]n_{o}=1.0748[/tex] (and slightly larger than that).

In point b, The only violet light is shown in the prism with the majority of the colors coming out from the sloping face for a scale similar to [tex]n_{o}= 1.0875[/tex] (and slightly smaller than this).

The left end of a spring is attached to a wall. When Bob pulls on the right end with a 200 N force, he stretches the spring by 20 cm. The same spring is then used for a tug-of-war between Bob and Carlos. Each pulls on his end of the spring with a 200 N force. How far does the spring stretch

Answers

Answer:

40 cm

Explanation:

Since Bob pulls with a force of F = 200 N when the spring is attached to the wall and it extends a length x = 20 cm, from Hooke's law,

F = kx where k = spring constant

So, k = F/x = 200 N/20 cm = 10 N/cm

Now, sine both Bob and Carlos pull with a force of F = 200 N in opposite directions, the spring stretches about its center and has an extension, x' in each direction.

So, from F = kx

x = F/k = 200 N/10 N/cm = 20 cm

So, the spring stretches 20 cm in both directions.

So, the total extension is thus x' + x' = 2x' = 2(20 cm) = 40 cm

The spring will stretch 40 cm.When a force is act om the spring the spring will stretch or compress depeds on the application of force.

What is hooke's law?

Hooke's law states that the force used to extend the spring is directly equal to the amount of stretch.

The force needed to extend the spring is proportional to its displacement. It is stated as

F=Kx

The given data in the problem is;

F is the force of pull to bob=  200 N

x is the length of extension= 20 cm.

F' is the force act on the another end=  200 N

According to Hooke's law,

[tex]\rm F = Kx \\\\ \rm K= \frac{F}{x} \\\\ \rm K= \frac{200}{20} \\\\ \rm K=10 \ N/cm[/tex]

The extension due to another end force is found by;

[tex]\rm x' = \frac{F}{K} \\\\ \rm x' = \frac{200}{10} \\\\ \rm x' = 20[/tex]

The total extension of the spring will be;

[tex]\rm x_t = x+x' \\\\ \rm x_t = 2(20) \\\\ \rm x_t =40\ cm[/tex]

Hence the spring will stretch 40 cm.

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please help me !!!! i really need it

Answers

Answer:

Prefer Soil more than sand

Explanation:

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