1. An airplane flies with an airspeed (speed relative to the air) of 215
km/h. The wind is blowing at 45.0 km/h. Find the velocity of the
plane (relative to the ground) if the plane is pointed straight west and
the wind is:

A. blowing toward the
west (3 points)

B. blowing toward the east (3 points)

C. blowing toward the south (4 points)
(For part C be sure to calculate the angle as well.)

Answers

Answer 1

Answer:

Explanation:

A) 215 + 45.0 = 260 km/h West

B) 215 - 45.0 = 170 km/h West

C) √(215² + 45.0²) = 219.6588... 220 km/h

θ = arctan(45.0/215) = 11.8214... 11.8° S of W

Answer 2

The airplane's ground velocity is westward at 170 km/h regardless of wind direction. The south wind does not affect the plane's westward velocity in component C.

Vector addition will determine each scenario's plane velocity relative to the ground. We'll simplify by assuming a consistent horizontal breeze.

Let's divide the airplane's velocity and wind velocity into westward (negative) and eastward (positive) components.

Data: Plane airspeed = 215 km/h.

45 km/h wind.

A. West wind:

The airplane's westward (negative) ground velocity:

West aeroplane velocity = -215 km/h

-45 km/h west wind.

Find Vg when the wind blows west:

Vg (west) = Aeroplane velocity + Wind velocity (west)

Vg(west) = -215 km/h - (-45 km/h)

Vg (west)=-170 km/h

B. East wind: 2. Westward (negative) aeroplane velocity relative to the ground:

West aeroplane velocity = -215 km/h

Wind velocity (east) = 45 km/h (because the wind is blowing eastward)

Find Vg when the wind blows east:

Vg (west) = Aeroplane velocity (west) + Wind velocity (east).

Vg (west) = -215 + 45 km/h

Vg (west)=-170 km/h

C. Southerly wind: 3. Westward (negative) aeroplane velocity:

West aeroplane velocity = -215 km/h

Wind velocity (south) = 0 km/h (no effect since wind is not moving westward)

Find Vg when the wind blows south:

Vg (west) = Aeroplane velocity (west) + Wind velocity (south).

Vg (west) = -215 + 0 km/h.

Vg (west)=-215 km/h

All resultant velocities are westward and 170 km/h.

Part C's plane's westward velocity is unaffected by the south wind. The plane's ground velocity remains -215 km/h (westward). Since the heading is westward, no angle is needed.

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Related Questions


17. The shape of a river is determined by which of the following? (Choose all that
apply)
A Erosion
B. Deposition
C. Weathering
D. water speed

Answers

Answer:

Water speed Plays a key role In determining The shape of it

If a force of 50 Newton's was applied to an object with a mass of 5 kilograms, what will the object's acceleration be?

Answers

Here’s my work to your question. I used Newton’s Second Law.
Force = mass * acceleration

A force of 50 N was applied to an object with a mass of 5 kg, then the acceleration of the object will be 10 m/s².

What is Acceleration?

The rate of change in an object's velocity with respect to time is known as acceleration in mechanics. The vector quantity of accelerations. The direction of the net force that is acting on an object determines its acceleration.

Since acceleration has both a magnitude and a direction, it is a vector quantity. Velocity is a vector quantity as well. The definition of acceleration is the change in velocity vector over a time interval divided by the time interval.

There are several types of acceleration :

Uniform AccelerationNon-Uniform AccelerationAverage Acceleration

According to the question, the given values are :

Force, F = 50 N

Mass, m = 5 kg

Force = m × a

a = 50 / 5

a = 10 m/s².

Hence, the acceleration of the object will be 10 m/s².

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How many valence electrons do most stable atoms have?

A) one

B) two

C) four

D) eight

Answers

Answer:

D) 8

Explanation:

Due to the octet rule the most stable atoms will have 8 valence electrons.

Which phrase describes the energy transformation that happens in a
generator?
A. Electrical energy into chemical energy
ООО
B. Electrical energy into mechanical energy
C. Chemical energy into electrical energy
O
D. Mechanical energy into electrical energy
SI

Answers

Answer:

Mechanical energy into electrical energy

Explanation:

Answer:

ExplanMechanical energy into electrical energy

SIation:

2. What is the oxidation number of oxygen in most compounds?
A. 6
B.-2
C. 8
D.O

Answers

Answer:i am pro

kExplanation:

The answer is b -2. Why because it’s electrically neutral compound

a hairdryer is used for 600 seconds to dry hair. it has a 750 watt rating. how much work did the hairdryer do

Answers

The amount of work done by the hairdryer is equal to 450 Kilojoules.

Given the following data:

Time = 600 secondsPower = 750 watt

To determine the amount of work done by the hairdryer:

Mathematically, the work done by an object with respect to power and time is given by the formula:

[tex]Work\;done = power \times time[/tex]

Substituting the given parameters into the formula, we have;

[tex]Work\;done = 750 \times 600[/tex]

Work done = 450,000 Joules

Note: 1000 Joules = 1 Kilojoules.

Work done = 450 Kilojoules.

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3. Particles carrying no charge ____________

Answers

Answer:

Neutrons

Explanation:

The graph below shows the variation with distance r from the nucleus of the square of the wave function, Ψ^2, of a hydrogen atom according to Schrödinger theory.
A. is most likely to be near a.
B. is always a.
C. is always less than a.
D. is always greater than a.

Answers

The region a represents the distance of the electron from the nucleus.

According to the wave mechanical model of the atom, the probability of finding an electron within a given volume element (representing the atom) is the square of the wave function psi.

Since a is the region in space where there is the greatest probability of finding the electron in the atom, it follows that distance of the electron form the atom is always a.

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A physics professor leaves her house and walk along the sidewalk toward campus. After 5 min it starts to rain and she returns home. Her distance from her house as a function of time shown in figure: 1. At which of the labelled point is her velocity (a) zero? (b) Constant and positive? (c) constant and negative ? (d) Increasing in magnitude? (e) Decreasing in magnitude?

Answers

Answer: I think its zero-

I dont really know about this...

a spring with a spring constant of 65 n/m is displaced -94cm. what is the magnitude of the force exerted by the spring

Answers

Answer:

Explanation:

F = kx = 65 N/m(0.94 m) = 61.1 = 61 N

7. Which of the following explains how radiometric dating is used to estimate absolute
age.
a. By comparing how deep in the curst the radioactive material in a sample of rock
is, scientists can calculate the length of time since the rock formed.
b. By comparing the amount of organic material in a sample of rock, to the known
rate of decay of the parent rock, scientists can calculate the length of time since
the rock formed.
C. By comparing the amount of radioactive material in a sample of rock, to the
surrounding rocks, scientists can calculate the length of time since the rock
formed.
d. By comparing the amount of a radioactive material in a sample of rock, to the
know rate of decay of the parent rock, scientists can calculate the length of time
since the rock formed.

Answers

Answer:

d.

Explanation:

Radiometric dating is a method of dating geological/ archaeological specimens by determining the relative proportions of particular radioactive isotopes present in a sample. Carbon dating is a form of radiometric dating, but, in choice b, you're not comparing the carbon to the rock. One would compare ¹⁴C levels within the organic compound, just as one would compare radioactive isotope levels in a rock.

An ammeter has azero offset error This fault will affect

Answers

Answer:

An ammeter has a zero offset error. This fault will affect. neither the precision nor the accuracy of the readings. only the precision of the readings.

The accuracy of the present measurement will be impacted by an ammeter's zero offset inaccuracy, but the precision of the measurement will not change.

What is resistance?

Resistance is the obstruction of electrons in an electrically conducting material.

                                                                                         

voltage = current ×resistance

How accurate measurement or reading is may be determined by its accuracy. The measurements will be off because of zero inaccuracy.

Thus, The precision of the measurement would not alter if an ammeter made a mistake with its zero offsets, but the accuracy of the current measurement would be decreased.

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If the speed of the magnet is doubled, the induced voltage is ________ . twice as great four times as great half as great unchanged

Answers

If the speed of the magnet is doubled, the induced voltage is twice as great

Faraday's law of induction states that whenever relative motion exists between a coil and magnetic field, a voltage will induce in the circuit and this voltage is proportional to the rate of change of the flux. The expression for the motional emf is as follows:

ε=Blv

Here, ε is the motional emf, B is the magnetic field, l is the length of the conductor, and v is the velocity at which the magnetic field changes.

The induced voltage by the moving magnet is directly proportional to the speed of the magnet. Therefore, an increase in the speed of the magnet will increase the induced voltage.

If the speed of the magnet is doubled, the induced voltage is twice as great

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A 0.050 kg metal bolt is heated to an unknown initial temperature. It is then dropped into calorimeter containing 0.15 kg of water with an initial temperature of 21.0°C. The bolt and the water then reach a final temperature of 25.0°C. If the metal has a specific heat capacity of 899 J/kg•°C, find the initial temperature of the metal.

Answers

The initial temperature of the metal bolt is 80.8 °C

We'll begin by calculating the heat absorbed by the water.

Mass of water (M) = 0.15 Kg Initial temperature (T₁) = 21 °CFinal temperature (T₂) = 25 °CChange in temperature (ΔT)  = T₂ – T₁ = 25 – 21 = 4 °CSpecific heat capacity of water (C) = 4184 J/KgºCHeat absorbed (Q) =?

Q = MCΔT

Q = 0.15 × 4184 × 4

Q = 2510.4 J

Finally, we shall determine the initial temperature of the metal bolt.

Heat absorbed by water = 2510.4 JHeat released by metal (Q) = –2510.4 JMass of metal (M) = 0.050 Kg Final temperature (T₂) = 25 °CSpecific heat capacity of metal (C) = 899 J/Kg°CInitial temperature (T₁) =?

Q = MC(T₂ – T₁)

–2510.4 = 0.050 × 899 (25 – T₁)

–2510.4 = 44.95 (25 – T₁)

Clear bracket

–2510.4 = 1123.75 – 44.95T₁

Collect like terms

–2510.4 – 1123.75 = –44.95T₁

–3634.15 = –44.95T₁

Divide both side by –44.95

T₁ = –3634.15 / –44.95

T₁ = 80.8 °C

Thus, the initial temperature of the metal is 80.8 °C.

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True or False. Father of a multitude" obeyed God's command to kill His son because the Ten Commandments had not yet been given.

Answers

Answer:

Explanation:

The father of the Multitude was Abraham. And he did precede the 10 commandments. But the story really has nothing to do with the 10 commandments.

He obeyed God's Command because it was God who issued it. Abraham had complete faith in God's ability to make things come out right. The sacrifice of Isaac was a test of faith.

I would advise you to answer true, but whoever wrote the question employed a twisted kind of logic. The sacrifice of Isaac had nothing to do with the 10 commandments. Thou Shalt not murder is not really covered by this circumstance.

So true might not be the correct answer. The question is very complex and does not lend itself to a simple True/ False answer.

A block slides on a rough 45 degree incline. The coefficient of friction is µk what is the ratio of acceleration when the block accelerates down the incline to the acceleration when the block is projected up the incline​

Answers

it is the same, force diagram is the same, acceleration depends on forces. the only thing different is the initial velocity.

Answer:

[tex]\frac{a_{d}}{a_{i}} = \frac{(1 -mu)}{mu}[/tex]

= (1 - μ)/μ

Explanation:

Always draw a diagram!

Up the incline:

[tex]Fr_{max}[/tex] = maximum friction

[tex]Fr_{max}[/tex] = μk

k = R = mg.cos(45) = mg.sin(45)

Resolution of forces parallel to the slope:

F (Fp in the diagram) = force of propulsion

g = gravity

[tex]F - Fr_{max} = ma_{i}[/tex]

[tex]F -[/tex] μ.mg.cos(45) [tex]= ma_{i}[/tex]

Down the decline:

Resolution of forces:

[tex]mg.sin(45) - Fr_{max} = ma_{d}[/tex]

[tex]mg.sin(45) -[/tex] μ.mg.cos(45) [tex]= ma_{d}[/tex]

Then, find the ratio:

[tex]\frac{ma_{d}}{ma_{i}} = \frac{mg.sin(45) - mu.mg.cos(45)}{-F + mu.mg.cos(45)} \\\\ \frac{a_{d}}{a_{i}} = \frac{k - k.mu}{-F + k.mu} \\\\ = \frac{k(1 -mu)}{-F + k.mu}[/tex]

Potentially, there is no need to consider F in this situation, in which case:

[tex]\frac{a_{d}}{a_{i}} = \frac{k(1 -mu)}{k.mu} \\\\ = \frac{(1 -mu)}{mu}[/tex]

= (1 - μ)/μ

A first order reaction is 25% completed in 1h minutes. Calculate the time required for its 50% completion.

Answers

It would be 2 hours I think

how big is earth
today​

Answers

Answer:

3,958.8 mi

Explanation:

A woman skis from rest down a hill 20 m high. If friction is negligible, what is her speed at the bottom of the slope? Select one: O a. 20 m/s O b. 12 m/s O c. 400 m/s O d. 6 m/s​

Answers

Hi there!

We can use the work-energy theorem to solve.

Recall:

[tex]\large\boxed{E_i = E_f}}[/tex]

Initial energy = final energy

The initial energy is purely potential (she starts from rest), and, if we assign the bottom of the slope as the 0 line, her energy at the bottom is purely kinetic.

PE = mgh

KE = 1/2mv²

We can begin by setting the two equal:

mgh = 1/2mv²

Cancel out the mass and rearrange to solve for velocity:

2gh = v²

v = √2gh

Plug in given values and use g ≈ 10 m/s²:

v = √2(10)(20) = 20 m/s

A swimmer who can swim in still water at a speed of 4km/h is swimming in a river. the river flows at a speed of 3km/h. calculate the speed of the swimmer relative to the river bank when she swims:- 1. downstream 2.upstream​

Answers

Explanation:

Downstream: you just sum the magnitude of the velocity vectors:

3km/h + 4km/h = 7km/h

Upstream: difference of the magnitudes of the velocity vectors, in absolute value:

|3km/h - 4km/h| = 1km/h

Make a generalization about Earth's magnetic field and its properties. In not more than 10 sentences.​

Answers

Answer:

Earth's magnetic field (and the surface magnetic field) is approximately a magnetic dipole, with the magnetic field S pole near the Earth's geographic north pole (see Magnetic North Pole) and the other magnetic field N pole near the Earth's geographic south pole (see Magnetic South Pole). This makes the compass usable for navigation. The cause of the field can be explained by dynamo theory. A magnetic field extends infinitely, though it weakens with distance from its source. The Earth's magnetic field, also called the geomagnetic field, which effectively extends several tens of thousands of kilometres into space, forms the Earth's magnetosphere. A paleomagnetic study of Australian red dacite and pillow basalt has estimated the magnetic field to be at least 3.5 billion years old

This is physics and it says collision and elastic/inelastic i need help

Answers

The initial velocity of the 3250 Kg mass is 2.1 m/s. The distance covered by the larger mass in 5s is 4.7 cm.

In this problem, we have to apply the law of conservation of linear momentum. Note that;

Momentum before collision = Momentum after collision

m1u1 + m2u2 = m1v1 + m2v2

(2150 × 10) + (3250u1) = (2150 + 3250)5.22

21500 + 3250u1 = 5400 × 5.22

3250u1  = 28188 - 21500

u1 = 28188 - 21500/3250

u1 = 2.1 m/s

2) Again from the principle of conservation of linear momentum;

(0.40 × 3.5) + (0.60 × 0) = (0.40  × 0.70) + (0.60 × v2)

1.4 = 0.28 + 0.60v2

1.4 - 0.28 =  0.60v2

v2 = 1.87 cm/s

Using;

s = 1/2 ( u + v)t

s = 1/2(0 + 1.87) × 5

s = 4.7 cm

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if the force acting on a body of mass 40 k.g is doubled by how much will the acceleration change​

Answers

Answer:

Explanation:

Ignoring friction, the acceleration will double

F = ma

2F = m(2a)

What is the average momentum of Cart 1 during the entire time shown before
kg-m
the collision, in units .?
$
Note that the collision appears to take place somewhere between 0.5 s and 0.6
s (perhaps at 0.6 s exactly, but we cannot be sure), so we can safely say that
data up to and including 0.5 s is "before the collision."

Answers

The average momentum of Cart 1 during the entire time shown before the collision is 0.24 kgm/s.

The given parameters:

Mass of the cart 1 = 500 g = 0.5 kg

The average velocity of the cart 1 before collision is calculated as follows;

[tex]v = \frac{\Delta x}{\Delta t} \\\\v = \frac{0.55 - 0.31}{0.5 - 0} \\\\v = 0.48 \ m/s\\\\[/tex]

The average momentum of Cart 1 during the entire time shown before the collision is calculated as follows;

[tex]P = mv\\\\P = 0.5 \times 0.48\\\\P = 0.24 \ kgm/s[/tex]

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A wire that is 1.0 m long with a mass of 90 g is under a tension of 710 N. When a transverse wave travels on the wire, its wavelength is 0.10 m. What is the frequency of this wave? ​

Answers

Answer:

890 Hz

I hope you liked my answer. Thank You!

6. A man with a mass of 75 kg standing on a skateboard is holding a medicine ball that has
a mass of 20 kg. If the man throws the ball to the left with a speed of 10 m/s,
a) What happens to the man on the skateboard?
b) What is the man's speed after throwing the ball?

Answers

Answer:

Explanation:

Conservation of momentum

a) the man and skateboard move to the right.

b) His speed depends on the reference frame of the ball speed.

If the speed of the ball is 10 m/s relative to ground and the man's final speed is v, then.

(75 + 20)(0) = 20(10) + 75(v)

v = -200/75 = -2.6666...

|v| = 2.7 m/s relative to the ground

This is the likely answer they are seeking.

If the ball is thrown with a speed of 10 m/s relative to the man

(70 + 20)(0) = 20(v + 10) + 75v

20v + 200 = - 75v

          200 = - 95v

               v = -2.105... m/s velocity or a speed of

              |v| = 2.1 m/s relative to ground

and the ball has a velocity of 10 - 2.1 = 7.9 m/s relative to ground.

the driver of a 2.0 × 10³ kg red car traveling on the highway at 45m/s slams on his brakes to avoid striking a second yellow car in front of him, which had come to of because locking ahead.After the brakes are applied a constant friction force of 7.5 × 10³ N acts on the car ignore air resistance.

a₎ Determine the least distance should the brakes be applied to avoid a collision with the other vehicle?

Answers

Answer:

Explanation:

a = F/m = 7500/2000 = 3.75 m/s²

v² = u² + 2as

s = (v² - u²) / 2a

s = (0² - 45²) / (2(-3.75))

s = 270 m

A 4.0-mF capacitor initially charged to 50 V and 6.0-mF capacitor charged to 30 V are connected to each other with the positive plate of each connected to the negative plate of the other. what is the final charge of the 6.0-mF capacitor?

a. 20 mC
b. 8.0 mC
c. 10 mC
d. 12 mC
e. 230 mC

Answers

[tex]\huge\color{pink}\boxed{\colorbox{black}{Answer ☘}}[/tex]

12 mC

Explanation:

We are given that...

[tex]C_{1} = 4mF \\ V_{1} = 50v \\ C_{2} = 6mF \\ V_{2} = 30v \\ \\ we've \: to \: find \: the \: final \: charge \: on \: the \: 6mF \\capacitor \:- \\ \\ we \: know \: that ,\: \\ Q = CV \\ \\ using \: the \: formula \: \\ Q_{1} = 4 \times 50 = 200mC \\ Q_{2} = 6 \times 30 = 180mC \\ \\ total \: charge , \: Q_{1} - Q_{2} = 200 - 180 = 20mC \\ \\ let \: V \: be \: the \: final \: potential \: \\ 4V + 6V = 20mC\\ 10V = 20mC \\ V = \frac{20}{10} = 2V \\ final \: charge \: Q = CV = 6 \times 2 = 12mC[/tex]

therefore,

σptíσn ( d ) íѕ cσrrєct!

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The force as a function of displacement of a moving object is presented by the graph. How much work is done when the object moves from 5 m to 8 m? *

Answers

Answer:

Explanation:

Work is the area under the curve between the limits

W = ½(5)(8 - 5) = 7.5 J

The work done when an object moves from 5 m to 8 m is 7.5 J.

Work done

The work done in moving an object from one point to another is equal to the product of force and displacement of the object.

W = Fs

Area under a curve

The work done on an object is equal to area under the curve

The area between point 5 m and 8 m = ¹/₂ x (8 - 5) x 5 = 7.5 J

Thus, the work done when an object moves from 5 m to 8 m is 7.5 J.

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Two Blocks are connected by a massless rope over a massless,
frictionless pulley, as shown in the figure. The mass of block 2
is m2 = 10.1 kg, and the coefficient of kinetic friction
between block 2 and the incline is Mk = 0.200. The angle 0 of
the incline is 27.5º. If block 2 is moving up the incline at
constant speed, what is the mass mi of block 1?

Answers

The mass of block 1 will be 1.99 kg.The tension force is applied along the whole length of the wire, pulling energy equally on both ends.

What is tension force?

The tension force is described as the force transferred through a rope, string, or wire as it is pulled by opposing forces.

Given that,

Mass of block 1=? kg

The coefficient of the kinetic friction,μ=0.200

Now consider the weight component in the uphill direction.The weight is found as;

[tex]\rm W=m_1gsin \theta[/tex]

The force is balanced in the vertical direction as;

[tex]\rm T=F_f-W[/tex]

When the force of friction is;

[tex]\rm F_F=\mu_k N[/tex]

[tex]\rm F_f=(m_1 gcos \theta)[/tex]

Substitute the value in the vertical balanced equation;

[tex]\rm T=m_1gsin(27.5)^0-\mu_kmgcos27.5^0[/tex]

[tex]\rm T-m_2g=0\\\\T=m_2g[/tex]

[tex]\rm (10.1) g=m_1g(0.699-0.2 \times(-0.714) ) \\\\ (10.1) g=m_1g (0.699+0.1428) \\\\\ (10.1) g= m_1 \times 0.8418 \\\\ m_1 =11.99 \ kg[/tex]

Hence the mass of block 1 will be 1.99 kg.

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