Give examples of motion in which the directions of the velocity and acceleration vectors are (a) opposite, (b) the same, and (c) mutually perpendicular​

Answers

Answer 1

Answer:

a) When moving body applies brake then velocity and acceleration would be in opposite direction

b) When body starts to increase velocity then velocity and acceleration would be in same direction

c) When body is circulating then velocity and acceleration would be perpendicular to each other

Explanation:

a) When body applies brake then its velocity starts decreasing, in this case its acceleration would try to stop the moving body. So direction of velocity would be same as direction of motion of body but direction of acceleration would be in opposite direction

b) When body starts to increase velocity, its acceleration would make the body to move faster. So direction of velocity would be the direction of motion of body and acceleration would also be in same direction

c) When body moves in circular path then its acceleration would be towards centre of circle and velocity would try to snap the body out of circle to straight line which in tangent to circle.


Related Questions

Consider two oppositely charged, parallel metal plates. The plates are square with sides L and carry charges Q and -Q. What is the magnitude of the electric field in the region between the plates

Answers

Answer:

 E = [tex]\frac{Q}{L^2 \epsilon_o}[/tex]

Explanation:

For this exercise we use that the electric field is a vector, so the resulting field is

          E_total = E₁ + E₂                      (1)

since the field has the same direction in the space between the planes

Let's use Gauss's law for the electric field of each plate

Let's use a Gaussian surface that is a cylinder with the base parallel to the plate, therefore the normal to the surface and the field lines are parallel and the angle is zero so cos 0 = 1

          Ф  = ∫ .dA = [tex]q_{int}[/tex] /ε₀

if we assume that the charge is uniformly distributed on the plate we can define a charge density

         σ = q_{int} A

             

as the field exists on both sides of the plate on the inside

          E A = A σ / 2ε₀

          E = σ / 2ε₀

           

we substitute in equation 1

         E = σ /ε₀

for the complete plate

         σ = Q / A = Q / L²

         

we substitute

         E = [tex]\frac{Q}{L^2 \epsilon_o}[/tex]

Which best describes what occurs when an object takes in a wave as the wave hits it?

A. transmission
B. absorption
C. reflection
D. refraction

Answers

Answer:

B

Explanation:

ABSORPTION

The following are ways to properly manage your stress except

Answers

Answer:

you should provide the options for us to answer?

write a note on unity of ant​

Answers

Answer: When a pathogen enters their colony, ants change their behavior to avoid the outbreak of disease. In this way, they protect the queen, brood and young workers from becoming ill. These results, from a study carried out in collaboration between the groups of Sylvia Cremer at the Institute of Science and Technology Austria (IST Austria) and of Laurent Keller at the University of Lausanne, are published today in the journal Science.

Explanation: search for it.

After a successful experiment involving the Sun, an astrophysicist proposes a theory for how stars change during the course of their existence. Is the astrophysicist correct in doing this

Answers

Answer:

Yes

Explanation:

A scientific theory is an explanation of a natural phenomenon based on available facts. If an Astrophysicist (a scientist who studies the universe and its celestial constituents) performs several successful experiments about a natural body like the sun and tests the results of his experiment using the principles of maths and physics and they come out as true, then he can propose a scientific theory based on his findings.

Unlike a scientific law that simply states a fact, a scientific theory provides evidence and explanation to support the facts.

Two wires are made of the same material and have the same length but different radii. They are joined end-to- end and a potential difference is maintained across the combination. Of the following quantities that is same for both wires is
A. Potential difference
B. Electric current
C. Current density
D. Electric field

Answers

Answer:

Current

I think The choose (B)

B. Electric current

Hellohellp fastttttttttt

Answers

Answer:

Explanation:

[tex]w_f^2=w_o^2-2\alpha\theta\\\\0=w_o^2-2\alpha\theta\\\\\theta={w_o^2\over{2\alpha}}[/tex]

[tex]w_o=2\pif=2\pi*8Hz=16\pi{rad\over{s}}\\\\\alpha=2.2{rad\over{s^2}}\\\\\theta={(16\pi{rad\over{s}})^2\over{2*2.2{rad\over{s^2}}}}=574.23rad[/tex]

[tex]revolutions={\theta\over{2\pi}}={574.23\over{2\pi}}=91.39[/tex]

A stone dropped from the top of a 80m high building strikes the ground at 40 m/s after falling for 4 seconds. The stone's potential energy with respect to the ground is equal to its kinetic energy … (use g = 10 m/s 2)
A) at the moment of impact.
B) 2 seconds after the stone is released.
C) after the stone has fallen 40 m.
D) when the stone is moving at 20 m/s.

At the moment of impact both Kinetic Energy and Potential Energy should be 0, right? So it can't be A), right? Or is this wrong? Is it indeed A)? Please show work and explain it well.

Answers

Answer: c. 40m

Explanation:

See picture

Wind instruments like trumpets and saxophones work on the same principle as the "tube closed on one end" that we examined in our last experiment. What effect would it have on the pitch of a saxophone if you take it from inside your house (at 76 degrees F) to the outside on a cold day when the outside temperature is 45 degrees F ?

Answers

Answer:

 f = v / 4L

the frequency of the instruments is reduced by the decrease in the speed of the wave with the temperature.

Explanation:

In wind instruments the wave speed must meet

          v = λ f

          λ = v / f

from v is the speed of sound that depends on the temperature

          v = v₀ [tex]\sqrt{1+ \frac{T [C]}{273} }[/tex]

where I saw the speed of sound at 0ºC v₀ = 331 m/s  the temperature is in degrees centigrade, we can take the degrees Fahrenheit to centigrade with the relation

            (F -32) 5/9 = C

            76ºF = 24.4ºC

            45ºF = 7.2ºC

           

With this relationship we can see that the speed of sound is significantly reduced when leaving the house to the outside

at T₁ = 24ºC               v₁ = 342.9 m / s

at T₂ = 7ºC                 v₂ = 339.7 m / s

To satisfy this speed the wavelength of the sound must be reduced, so the resonant frequencies change

              λ / 4 = L

              λ= 4L

              v / f = 4L

              f = v / 4L

Therefore, the frequency of the instruments is reduced by the decrease in the speed of the wave with the temperature.

A charged particle of mass 0.0040 kg is subjected to a magnetic field which acts at a right angle to its motion. If the particle moves in a circle of radius at a speed of what is the magnitude of the charge on the particle

Answers

Complete Question

A charged particle of mass 0.0040 kg is subjected to a 40-T magnetic field which acts at a right angle to its motion. If the particle moves in a circle of radius 0.10 m at a speed of 20m/s, what is the magnitude of the charge on the particle?

Answer:

[tex]q=0.020C[/tex]

Explanation:

From the question we are told that:

Mass [tex]m=0.004kg[/tex]

Magnetic field [tex]B=40-T[/tex]

Radius [tex]r=0.10m[/tex]

Speed [tex]v= 20m/s[/tex]

Generally the equation for Radius of a circular path is mathematically given by

[tex]r=\frac{p}{qB}[/tex]

Where

[tex]p=mv[/tex]

Therefore

[tex]q=\frac{mv}{rB}[/tex]

[tex]q=\frac{0.004kg*20m/s}{0.1*40}[/tex]

[tex]q=0.020C[/tex]

I NEED HELP ASAP!!!
which of the following causes the magnetic force between the magnet and the scrap metal?

Answers

Answer:

Alternating current at which when entered into the loop cause it to magnetize

What is the rate of power flowing through phone if a 2.50V battery produces 1.50A of current?

Answers

Answer:

3.75 watts

Explanation:

power = volts * current

2.5 * 1.5 =

3.75

Can a conductor be given limitless charge

Answers

Answer:

No

Explanation:

You could try to give it enough to fill all valence electrons in all of the atoms in the conductor, but practically this could not be achieved.

A denser object will usually have a ____ index of
refraction.

Answers

Answer:

A denser object will usually have a high index of

refraction.

A denser object will usually have a high index of refraction.

What is index of refraction?

The refractive index is the ratio of the speed of light in vacuum and speed of light in any medium.

n = c/v

The density is greater for the denser medium (water, oil, mercury, etc) then the rarer medium (any gas or air).

When a light ray travels through denser medium, its velocity is reduced and the refracted ray bends towards normal.

As, the index of refraction is inversely proportional to the velocity of light in the medium, index of refraction will be high for denser object.

Thus, denser object have high index of refraction.

Learn more about index of refraction.

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Automobile A and B are initially 30 m apart travelling in adjacent highway lanes at speeds VA = 14.4 km/hr., VB 23.4 km/hr. at t = 0.0. Knowing that automobile A has a constant acceleration of 0.8 m/s? and automobile B has a constant deceleration of 0.4 m/s2. Automobile A will overtake B after traveling a distance SA: A B. Side view​

Answers

Answer:

        x = 240 m

Explanation:

This is a kinematics exercise

Let's fix our frame of reference on car A

           x = x₀ₐ+ v₀ₐ t + ½ aₐ t²

         

the initial position of car a is zero

           x = 0 + v₀ₐ t + ½ 0.8 t²

for car B

          x = x_{ob} + v_{ob} t - ½ a_b t²

     

car B's starting position is 30 m

         x = 30 + v_{ob} t - ½ 0.4 t²

at the point where they meet, the position of the two vehicles is the same

         0 + v₀ₐ t + ½ 0.8 t² = 30 + v_{ob} t - ½ 0.4 t²

let's reduce the speeds to the SI system

        v₀ₐ = 14.4 km / h (1000 m / 1 km) (1h / 3600s) = 4 m / s

        v_{ob} = 23.4 km / h = 6.5 m / s

        4 t + 0.4 t² = 30 + 6.5 t - 0.2 t²

        0.2 t² - 2.5 t - 30 = 0

        t² - 12.5 t - 150 = 0

we solve the quadratic equation

       t = [tex]\frac{12.5 \pm \sqrt{12.5^2 + 4 \ 150} }{2}[/tex]

       t = [tex]\frac{12.5 \ \pm 27.5}{2}[/tex]

       t₁ = 20 s

       t₂ = -7.5 s

time must be a positive quantity so the correct result is t = 20 s

let's look for the distance

        x = 4 t + ½ 0.8 t²

        x = 4 20 + ½ 0.8 20²

        x = 240 m

1. Consider a 1000 kg car rounding a curve on a flat road of radius 50 m at a speed of
50 km/h (14 m/s).
a. Will the car make the turn if the pavement is dry and the coefficient of static
friction is 0.60?​

Answers

Answer:

The car will make the turn perfectly

Explanation:

Given that the centripetal force= mv^2/r

M= mass of the car

v = speed of the car

r= radius

Hence;

F = 1000 × (14)^2/50

F= 3920 N

The frictional force = μmg

μ = coefficient of static friction

m= mass

g = acceleration due to gravity

Frictional force= 0.6 × 1000× 10

Frictional force = 6000 N

The car will not skid off the curve because the frictional force is greater than the centripetal force.

which of the following is correct for solids? a. y=2/3 alpha b.y= 2/3 bita c.y = 3/2 bita d.y=3/2 alpha​

Answers

option a ...

please mark hcfhvx

A cylindrical water tank has a height of 20cm and a radius of 14cm. If it is filled to 2/5 of its capacity, calculate.

I. Quantity of water in the tank

II. Quantity of water left to fill the tank to its capacity.

Answers

Answer:

4.926 L Y 7.389 L

Explanation:

first you calculate the tank volume

V = π[tex](14 cm)^{2}[/tex](10 cm = [tex]12315 cm^{3}[/tex]

then you convert to liters

[tex]12315 cm^{3}[/tex] = 12.315 l

then you calculate the liters of water

2/5(12.35 l) = 4.926 l

finally we calculate the amount without water

12.315 l - 4.926 l = 7.389 l

HERE IS MORE INFORMATION ON THE SUBJECT. THEY REMOVED THE

ENGLISH SITE BUT YOU CAN USE TRANSLATOR

LINK: https://gscourses.thinkific.com/courses/fisicai

A car starting at rest accelerates at 3m/seconds square How far has the car travelled after 4s?​

Answers

Answer:

24 meters

Explanation:

Find the final velocity. 12m/s

d=[final-initial]/2×time

D=(6m/s)×4=24 m/s

A source of emf is connected by wires to a resistor and electrons flow in the circuit the wire diameter is teh same throughout teh circuit compared to the drift speed of the electrons before entering the source of emf, the drift speed ot eh electrons afte rleaving the source of emf is: ___________

a. faster.
b. slower.
c. the same.
d. either A or B depending on circumstances.
e. any of A, B , or C depending on circumstances.

Answers

I think is E
I hope that helps

A 1.8-m-tall diver is standing completely submerged on the bottom of a swimming pool, in 3.0 m of water. You are sitting on the end of the diving board, almost directly over her.

Required:
How tall does the diver appear to be?

Answers

Answer:

[tex]H=1.35m[/tex]

Explanation:

From the question we are told that:

Height [tex]h=1.8m[/tex]

Depth of Water [tex]d=3.0m[/tex]

Where

Refraction index of water [tex]n = 4 / 3[/tex]

Generally the equation for Apparent height of the diver  is mathematically given by

[tex]H=h\frac{h}{n}[/tex]

[tex]H=\frac{1.8}{\frac{4}{3}}[/tex]

[tex]H=1.35m[/tex]

Which two factors does the power of a machine depend on? А. work and distance B.. force and distance C. work and time D. time and distance?​

Answers

[tex]Hello[/tex] [tex]There![/tex]

[tex]AnimeVines[/tex] [tex]is[/tex] [tex]here![/tex]

The answer is...

C. Work and time.

[tex]HopeThisHelps!![/tex]

[tex]AnimeVines[/tex]

Suppose you want to design an air bag system that can protect the driver at a speed 100 km/h (60 mph) if the car hits a brick wall.
Estimate how fast the air bag must inflate to effectively protect the driver. How does the use of a seat belt help the driver?

Answers

When solving question that contains equations and the use mathematical computations, It is always ideal to list the parameters given.

Now, given that:

the speed of the car which is the initial velocity (u) = 100 km/h before it hits the wall.after hitting the wall, the final velocity will be (v) = 0 km/h

Assumptions:

Suppose we make an assumption that the distance traveled during the collision of the car with the brick wall (S) = 1 mThat the car's acceleration is also constant.

For a motion under constant acceleration, we can apply the kinematic equation:

[tex]\mathsf{v^2 = u^2 + 2as}[/tex]

where;

v = final velocity u = initial velocitya = accelerations = distance

From the above equation, making acceleration (a) the subject of the formula:

[tex]\mathsf{v^2 - u^2 =2as }[/tex]

[tex]\mathsf{a = \dfrac{v^2 - u^2 }{2s}}[/tex]

The initial velocity (u) is given in km/h, and we need to convert it to m/s as it has an effect on the unit of the acceleration.

since 1 km/h = 0.2778 m/s

100 km/h = 27.78 m/s

[tex]\mathsf{a = \dfrac{(0)^2 - (27.78)^2 }{2(1)}}[/tex]

[tex]\mathsf{a = \dfrac{- 771.7284 }{2}}[/tex]

a = - 385.86 m/s²

Similarly, from the kinematic equation of motion, the formula showing the relation between time, acceleration, and velocity is;

v = u + at

where;

v = 0

-u = at

[tex]\mathsf{t = \dfrac{-u}{a}}[/tex]

[tex]\mathsf{t = \dfrac{-27.78}{-385.86}}[/tex]

t = 0.07 seconds

An airbag is designed in such a way as to prevent the driver from hitting on the steering wheel or other hard substance that could damage the part of the body. The use of the seat belt is to keep the driver in shape and in a balanced position against the expansion that occurred by the airbag during the collision on the brick wall.

Thus, we can conclude that in order to estimate how fast the airbag must inflate to effectively protect the driver, the airbag must be inflated at 0.07 seconds faster before the collision to effectively protect the driver.

Learn more about the kinematic equation here:

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If the Velocity of the body
is increased to 3v, determine the kinetic energy

Answers

ANSWER; KE=5mv^2 so it is proportional to v^2.

Explanation:So if you triple the velocity you are replacing v with 3v. Then you get (3v)^2=9v^2.

During a particular thunderstorm, the electric potential difference between a cloud and the ground is Vcloud - Vground = 4.20 108 V, with the cloud being at the higher potential. What is the change in an electron's electric potential energy when the electron moves from the ground to the cloud?

Answers

Answer:

The electric potential energy is 6.72 x 10^-11 J.

Explanation:

Potential difference, V = 4.2 x 10^8 V

charge of electron, q = - 1.6 x 10^-19 C

Let the potential energy is U.

U = q V

U = 1.6 x 10^-19 x 4.2 x 10^8

U = 6.72 x 10^-11 J

Electromagnetic Wave PenetrationRadio waves and mircowaves are used in therapy to provide "deep heating" of tissue because the waves penetrate beneth the surface of the body and deposit energy. We define the penetration depth as the depth at which the wave intensity has decreased to 37% of its value at the surface. The penetration depth is 15cm for 27MHz radio waves. For radio frequencies such as this, the penetration depth is proportional to (sqrt of lambda), which is the square root of the wavelength. What is the wavelength of 27 MHz radio waves? A. 11 m.B. 9.0 m.C. 0.011 m.D. 0.009 m.If the frequency of the radio waves is increased, the depth of penetration:_____.A. Increases. B. Does not change. C. Decreases. 3. For 27 MHzMHz radio waves, the wave intensity has been reduced by a factor of 3 at a depth of approximately 15 cmcm. At this point in the tissue, the electric field amplitude has decreased by a factor of:____.A. 9 77. B. 3√3. C. 3. D. √3.

Answers

Answer:

Hence the square root of the wavelength. What is the wavelength of 27 MHz radio waves  11 m; option A is the correct answer.

Hence, as the frequency of the radio waves increases the penetration depth decreases.

Option C is the correct answer.

Hence the electric field amplitude has decreased by a factor of √3.

Hence the correct option is D.

Explanation:

[tex]c=n\lambda[/tex], where the symbols have their usual meanings.

[tex]\lambda =c/n\\= 3\times10^{8}/27\times10^{6}\\\\=11.11 m[/tex]

Hence, wavelength = 11 m; option A is the correct answer.

As given that, the penetration depth is proportional to the square root of wavelength, and we know that,

wavelength and frequency are inversely proportional to each other.

Hence, as the frequency of the radio waves increases the penetration depth decreases.

Option C is the correct answer.

Electric field amplitude is directly proportional to the square root of the intensity. Therefore, the ratio between the electric field amplitude is,

[tex]\frac{E\sigma_{1} }{E\sigma_{2} } =\sqrt{\frac{I_{1} }{I_{2} } }[/tex]

Here to find the ratio of intensities,

[tex]{\frac{I_{1} }{I_{2} } } = 3[/tex]

Therefore,

[tex]\frac{E\sigma_{1} }{E\sigma_{2} } =\sqrt{3 }[/tex]

Hence the correct option is D.

6. Two astronauts of equal mass step from the top of a rocket on Venus. One slides down a 10- degree ramp while the other slides down a 75-degree ramp. If all friction is ignored, which astronaut reaches the surface of Venus with the lower kinetic energy

Answers

Answer:

Final kinetic energies of both astronauts will be the same.

Explanation:

If we ignore all the friction present between the ramp and the person. Then essentially there is no loss of energy in the system. Hence the initial potential energies of the astronauts must be equal to their final kinetic energies.

Now the potential energy depends upon mass, height and acceleration due to gravity. All these parameters for both the astronauts. Therefore,both astronauts have same initial potential energies.

Similarly, the final kinetic energies of astronauts will also be the same.

Picture isn’t the best but could use the help

Answers

Answer:

60 deg from Y-axis is 150 deg from X-axis

x = L cos theta = 23,2 cos 150 = -.867 * 23.2 = -20.1

the coefficient of linear expansion of aluminum is 24.0 * 10^-6K^-1 and th density of aluminum at ) C is 2.7 *10^3kg/m^3. what is the density of aluminum at 300 C

Answers

Answer:

The density at 300 C is [tex]2641.68 kg/m^3[/tex].

Explanation:

density at 0 degree, d = 2700 kg/m3

coefficient of linear expansion, = 24 x 10^{-6} /K

Let the density at 300 C is d'.

Use the formula of the cubical expansion

[tex]d'= d (1-3\alpha \Delta T)\\\\d'= 2700(1- 3 \times 24\times 10^{-6}\times 300)\\\\d' = 2641.68 kg/m^3[/tex]

The top of a swimming pool is at ground level. If the pool is 2.60 m deep, how far below ground level does the bottom of the pool appear to be located for the following conditions?

a. The pool is completely filled with water.
______m below ground level

b. The pool is filled halfway with water.
______m below ground level

Answers

Answer:

a)  [tex]d_g=1.95m[/tex]

b) [tex]d_g'=2.3m[/tex]

Explanation:

From the question we are told that:

Depth [tex]d=2.60[/tex]

a)

Generally the equation for distance to ground is mathematically given by

[tex]\frac{d_g}{d}=\frac{1}{n}[/tex]

Where

[tex]n=\frac{4}{3}[/tex]

Therefore

[tex]d_g=\frac{d}{n}[/tex]

[tex]d_g=\frac{2.6}{4/3}[/tex]

[tex]d_g=1.95m[/tex]

b)

For when The pool is filled halfway with water

[tex]\frac{d_g}{d}=\frac{1}{n}[/tex]

[tex]d_g'=\frac{1.3}{4/3}[/tex]

[tex]d_g'=0.98m[/tex]

Therefore

[tex]d_g'=(1.3+0.98)[/tex]

[tex]d_g'=2.3m[/tex]

Other Questions
A cylindrical wire made of an unknown alloy hangs from a support in the ceiling. You measure the relaxed length of the wire to be 16 m long; and the radius of the wire to be 3.5 m. When hang a 5 kg mass from the wire, you measure that it stretches a distance of 4 x 10 m The average bond length between atoms is 2.3 x 10^0 m for th alloy. Required:What is the stiffness of a typical interatomic bond in the alloy Levi decides to examine the effect of fertilizer on the growth of tomato plants. He chooses four plants for his experiment and applies varying amounts of fertilizer to three of them. He does not apply fertilizer to one plant. Over a 15-day period, the plants receive fertilizer on Days 1, 4, 7, 10, and 13. Levi measures the height of all of his plants with a meterstick on Days 3, 6, 9, 12, and 15. He also makes sure to hold all experimental factors constant except for the fertilizer.What is the dependent variable in Levi's experiment on tomato plants?the amount of fertilizer given to the plantsthe measurements of plant heightthe days fertilizer was appliedthe days plant height was measured S=n/2(2a+(n-1)d). If d=5, n=13, S=585 find the value of a. What is the area of the pool ? Agile project management involves ____ whereas traditional project management involves _______. Multiple Choice known and stable scope, unknown requirements high certainty, projects with unstable scope projects with high predictability, project with unknown or unstable requirements iterative and incremental delivery, upfront planning with high predictability high uncertainty, projects with unknown requirements find the area of the following composite figure plz help me to slove this The median age (in years) of the U.S. population over the decades from 1960 through 2010 is given by f(t) = 0.2176t3 + 1.962t2 2.833t + 29.4 (0 t 5) where t is measured in decades, with t = 0 corresponding to 1960.(a) What was the median age of the population in the year 1970?(b) At what rate was the median age of the population changing in the year 1970? (c) Calculate f''(1). Quartz, or silicon dioxide (SiO2), is one of the most abundant minerals on Earth. The diagram shows the atomic arrangement of quartz. Based on the diagram, which statement best describes the atomic arrangement of quartz?Group of answer choicesAn extended structure that is made of repeating patterns of atoms.A repeating pattern of small molecules that can move freely past each otherMany different kinds of molecules tha combine to form an extended structure.Many different kinds of atoms that can move freely past each other. The Boeing777-300ER flies between Auckland and Los Angeles. It has 246 Economyclass seats, 50 Premium Economy seats and 44 Business Premier seats. Out of the 340seats in total, what percentage are Economy seats? what is flood and landslide ? write the major during or after time . find the missing side lengths why do we respect eavh other Choose the word or phrase that best completes the sentence.I enjoy watching snowboarding and ice skating in the Winter Olympics; __________, the Summer Games aren't as entertaining.that being saidby the same tokensimilarlybecause Given the arc, name the central angle. FGA. GQJB. FQGC. GQID. HQI CW:- 1. Read and correct these sentences: a. I comb my hairs. b. They eat a lot of meats. c. She drinks much waters. d. He has got much moneys. e. I drink a juice every day. HW:- 1. ..... of Mountain. 2. ..... of wolves. 3. ..... a loins. 4. ..... of soldiers. 5. ..... of oxen. 6. ..... of tourists. 7. ..... of antelope. How to do this twoplease help me with this Learning to move past disappointments or frustrations and work with the situation at hand best describes the stress-management strategy of being flexible being mindful of diet focusing on the good seeking help when needed what is logical evidence What are the uses of magnetic force? 8.113 as a fraction PLEASE HELP ME