A diet decreases a person's mass by 6 %. Exercise creates muscle and reduces fat, thus increasing the person's density by 1 %. Determine the percent change in the person's volume.

Answers

Answer 1

Answer:

-5%

Explanation:

We know that volume is mass/density

So to find percentage

Let first mass be = M1

Second be 0.94m( 1-6%)

Second density be=0.99

First density be d

So finlq volume v2= 0.94m/0.99p=

V2= (0.94/0.99)V1

V2= 0.95v1

So volume decrease will be 1-0.95= 0.05

= -5%


Related Questions

A typical atom has a diameter of about 1.0×10−10m.
Approximately how many atoms are there along a 2.0 −cm line?
Express your answer using two significant figures.

Answers

Answer:

10m

Explanation:

if it was at the 2.0 line it would be 10 m

If a typical atom has a diameter of about 1.0×10⁻¹⁰ m, then there are approximately atoms are there along a 2.0-centimeter line.

What are significant figures?

In positional notation, significant figures refer to the digits in a number that is trustworthy and required to denote the amount of something, also known as the significant digits, precision, or resolution.

As given in the problem If a typical atom has a diameter of about 1.0×10⁻¹⁰ m, then we have to find out approximately how many atoms are there along a 2.0-centimeter line,

diameter of the one atom =  1.0×10⁻¹⁰

approximate number of atoms in 2 cm line = 2 ×10⁻² /( 1.0×10⁻¹⁰ )

                                                                         =2 ×10⁸ atoms

Thus, there are approximately 2 ×10⁸ atoms are there along a 2.0-centimeter line.

Learn more about significant figures here,

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An engineer is designing a tire for heavy machinery which statement describes the clearest criterion for the solution

Answers

Answer:

I think B tell me if it's right

Explanation:

If an engineer is designing a tire for heavy machinery then a statement that describes the clearest criterion for the solution would be that it must function safely under the load of 4500 kg, therefore the correct answer is option C.

What is the mechanical advantage?

Mechanical advantage is defined as a measure of the ratio of output force to input force in a system, It is used to analyze the forces in simple machines like levers and pulleys.

Mechanical advantage = output force(load) /input force (effort)

As given in the problem statement that an engineer is designing a tire for heavy machinery and we have to find the statement which describes the clearest criterion for the solution,

As he is designing heavy machinery that must be able to support a large amount of weight,

Thu, the best option that is satisfying the criteria is option C.

Learn more about Mechanical advantages, here

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Aa commercial advertising a diet pill says it is scientifically proven to help you lose weight. It is recommended by a doctor who observed that some of his patients lost weight after taking the pill for a week. Why is this claim considered pseudoscience

Answers

Answer:

no more than 10 pills a day depending on what type it is

Explanation:

What line on a wheather map indicates áreas where the temperature is the same?

Answers

Answer:Isobars and isotherms

Explanation:

in an equation f = l^2-d^2/4l the intercept is

Answers

Answer:

the intercept is the orgin (0,0)

20 POINTS 20 POINTS On a bright sunny day you decide to take a walk. You begin at your home and walk 1000 meters to an ice cream shop in 10 minutes. You spend 15 minutes ordering your ice cream and then return home. Since you have an ice cream cone in your hand, it takes 20 minutes to walk home. 1. Find the total displacement and total distance traveled. 2. Find your average speed and average velocity in meters/min. 3. Find your average speed and average velocity in meters/sec.

Answers

Answer:

A) Total Distance = 2000 m and Total displacement = 0 m

B) Average Speed = 44.44 m/min and Average Velocity = 0 m/min

C) Average Speed = 0.7407 m/s and Average velocity = 0 m/s

Explanation:

A) Distance to reach ice cream shop from home = 1000 meters

Therefore distance to get back home would also be 1000 meters.

Total distance traveled = 1000 + 1000 = 2000 metres

Since journey started at home and ended at home, then total displacement = 0 metres.

B) Average speed = Total distance/total time.

Total time = 10 + 15 + 20 = 45 minutes

Since total distance = 2000 m

Then;

Average speed = 2000/45

Average speed = 44.44 m/min

Average velocity = Total displacement/total time

Average velocity = 0/45 = 0 m/min

C) We now want answers in B to be in m/s.

Total time = 45 minutes.

From conversion, 60 seconds make 1 minute. Thus, 45 minutes = 45 × 60 = 2700 seconds

Thus;

Average Speed = 2000/2700

Average Speed = 0.7407 m/s

Average displacement = 0/2700 = 0 m/s

How long did it take me to make this?

Answers

1hour because that takes a lot of time

Answer:

Its according from what it is made with if wax it takes longer but if with a craft paper it takes lesser time if paper approximately 20 to 25 minutes

The acceleration of a particle traveling along a straight line is
a=16s1/2 m/s2, where s is in meters.
If v = 0, s = 3 m when t = 0, determine the particle's velocity at s = 6 m.

Answers

Answer:

V= 14.2m/s

Explanation:

We know that acceleration= dv/dt

So 16m/s²=dv/ dt = v dv/ds

So this wil be

Integral of 16m/s² ds [at 2,2]= integral of v dv at[ 0, v]

So 16[s (3/2)/3/2] at ( s,3) = v²/2

At s= 6m

So v² = 64/3( 6^1.5-3^1.5)

= 14.2m/s

what is the difference between each distance traveled and displacement travled

Answers

Displacement is a vector magnitude that depends on the position of the body which is individualistic for the trajectory.

While, Distance is a scalar magnitude that measures over the trajectory.

A car accelerates in the +x direction from rest with a constant acceleration of a1 = 1.76 m/s2 for t1 = 20 s. At that point the driver notices a tree limb that has fallen on the road and brakes hard for t2 = 5 s with a constant acceleration of a2 = -5.93 m/s2.Write an expression for the car's speed just before the driver begins braking, v1.If the limb is on the road at a distance of 550 meters from where the car began its initial acceleration, will the car hit the limb?

Answers

Answer:

1) an expression for the car's speed is given as

v = u + at

where

v is the car's speed

u is the initial speed of the car

a is the car's acceleration

t is the time spent accelerating

2) The car does not hit the tree limb

Explanation:

The initial velocity of the car = 0 m/s  (since it accelerates from rest)

acceleration of the car = 1.76 m/s

time spent accelerating = 20 s

For the car's speed just before the driver begins braking, we use the expression

v = u + at

where v is the final speed of the car just before the driver begins braking

u is the initial velocity with which the car starts moving

a is the acceleration of the car

t is the time spent accelerating from u to v

substituting values, we have

v = 0 + 1.76(20)

v = 0 + 35.2

the car's speed v = 35.2 m/s

In this time the car accelerates, the car moves a distance given by

s = ut + [tex]\frac{1}{2}[/tex]a[tex]t^2[/tex]

where s is the distance covered in this time

u is the initial speed of the vehicle

a is the acceleration

t is the time taken

substituting, we have

s = 0(20) + [tex]\frac{1}{2}[/tex](1.76)[tex]20^{2}[/tex]

s = 0 + 352

distance s = 352 m

When the driver brakes, we have

time spent braking = 5 s

acceleration = -5.93 m/s

and the distance to the limb = 550 m from where the car begun

to get the distance covered in this period, we use the expression

s = ut + [tex]\frac{1}{2}[/tex]a[tex]t^2[/tex]

where s is the distance traveled at this time

u is the speed of the car before it starts braking = 35.2 m/s

a is the acceleration at this point

t is the time taken to decelerate to a stop

substituting values, we have

s = 35.2(5) + [tex]\frac{1}{2}[/tex](-5.93 x [tex]5^2[/tex])

s = 176 - 74.125

s = 101.88 m

Total distance moved by the car = 352 m + 101.88 m = 453.88 m

Since the total distance traveled by the car is less than the distance from the starting point to the place where the tree limb is, the car does not hit the tree limb.

an object is accelerating if it is moving____. circle all that apply. ​

Answers

Answer:

With changing speed and/or in a circle

What does it mean that a theory or model is workable?
PLEASEEEEEEEE HELP ME FAST ​

Answers

Answer:

model is viable if the assumptions that answer it are in accordance with the fundamental principles or laws of physics and if it gives conclusions that can be tested with experiments.

Explanation:

A model in physics must be verified by experiments that are carried out to measure the consequences derived from it.

A model is viable if the assumptions that answer it are in accordance with the fundamental principles or laws of physics and if it gives conclusions that can be tested with experiments. Models that meet these conditions are said to be viable

A fly enters through an open window and zooms around the room. In a Cartesian coordinate system with three axes along three edges of the room, the fly changes its position from point b (2.5 m, 2.0 m, 4.0 m) to point e (4.5 m, 3.0 m, 3.5 m). Find the scalar components of the flies displacement vector (in m).

Answers

Answer:

Explanation:

Displacement vector along x axes = 4.5 - 2.5 = 2 m

Displacement vector along y axes = 3 - 2 = 1 m

Displacement vector along z axis = 3.5- 4 = - 0.5 m

Displacement vector = 2 i + j - 0.5 k m

Find the magnitude of the magnetic field ∣∣B⃗ (r)∣∣ inside the cylindrical resistor, where r is the distance from the axis of the cylinder, in terms of i, r, r0, l, and other given variables. You will also need π and μ0. Ignore fringing effects at the ends of the cylinder.

Answers

Answer:

The magnetic field inside the cylindrical resistor is [tex]\dfrac{\mu_{0}ir}{2\pir_{0}^2}[/tex]

Explanation:

Given that,

Distance from the axis of the cylinder = r

We need to calculate the magnetic field inside the cylindrical resistor

Using formula of magnetic field

[tex]\oint{\vec{B}\cdot\vec{dl}}=\mu_{0}i_{encl}[/tex]

[tex]B\cdot(2\pi r)=\mu_{0}\dfrac{i\pir^2}{\pi r_{0}^2}[/tex]

Where, r₀ = radius

r = distance

i = current

[tex]|\vec{B}(r)|=\dfrac{\mu_{0}ir}{2\pir_{0}^2}[/tex]

Hence, The magnetic field inside the cylindrical resistor is [tex]\dfrac{\mu_{0}ir}{2\pir_{0}^2}[/tex]

I point
Is the car's speed increasing or decreasing with time?
not enough information
decrease
increase
constant

Answers

Answer:

It's increasing with time

It’s increasing b/c the dots are moving further

Peter left Town A at 13:30 and travelled towards Town B at an
average speed of 40 mph. At 13:45, Philip left Town A for Town
B at an average speed of 30 mph. What was the distance
between them at 15:00?

Answers

Answer:

Explanation: From 13:30 to 15:00, it past: 1 h 30 mins = 1.5

Then, the distance covered by Peter: 40x1.5= 60 miles

From 13:45 to 15:00, it pasts; 1 h 15min =1.25

Then, the distance covered by Philip. 30 x 1.25 = 37.5 miles

Lastly, the distance between them: 60-37.5= 22.5 miles

So the answer is 22.5

A sinusoidal electromagnetic wave from a radio station passes perpendicularly through an open window that has area of 0.500 m2 . At the window, the electric field of the wave has an rms value 0.0600 V/m .
How much energy does this wave carry through the window during a 30.0-s commercial? Express your answer with the appropriate units.

Answers

Answer:

The energy of the wave is 1.435 x 10⁻⁴ J

Explanation:

Given;

area of the window, A = 0.5 m²

the rms value of the field, E = 0.06 V/m

The peak value of electric field is given by;

[tex]E_o = \sqrt{2} *E_{rms}\\\\E_o = \sqrt{2}*0.06\\\\E_o = 0.0849 \ V/m[/tex]

The average intensity of the wave is given by;

[tex]I_{avg} = \frac{c \epsilon_o E_o^2 }{2}\\\\I_{avg} = \frac{(3*10^8)( 8.85*10^{-12}) (0.0849)^2 }{2}\\\\I_{avg} = 9.569*10^{-6} \ W/m^2[/tex]

The average power of the wave is given by;

P = I x A

P = (9.569 x 10⁻⁶ W/m²) (0.5 m²)

P = 4.784 x 10⁻⁶ W

The energy of the wave is given by;

E = P x t

E = (4.784 x 10⁻⁶ W)(30 s)

E = 1.435 x 10⁻⁴ J

Therefore, the energy of the wave is 1.435 x 10⁻⁴ J

Common benefits of lower body endurance include improved

Answers

Answer:

Hearing, Vision and Metabolism.

a car moves 8 m in 4 s at a comstant velocity. what is the cars acceleration

Answers

Answer:

Zero.

Explanation:

Acceleration is defined as change in velocity per unit time. For constant, the acceleration is zero.

      [tex]\hat{a} =\frac{ \delta V}{t}[/tex]

as [tex]\delta[/tex][tex]v\\[/tex] is zero.

Is the sinusoidal pattern on the string longer or shorter with a greater propagation velocity?

Answers

Answer:

Increase in velocity propagation would lead to a longer sinusoidal pattern.

Explanation:

The velocity of propagation has a relationship with the tension in a standing wave and is given by;

v = √(T/μ)

where:

μ is mass per unit length.

T is tension in string

For the sinusoidal pattern on the string to be longer or shorter, it means that the wavelength will be longer or shorter.

Now, relationship between wavelength and velocity and tension is;

v = λ/T

Where V is velocity of propagation, λ is wavelength and T is Tension.

So, λ = vT

From the earlier standing wave equation, we will see that if we increase the velocity, it means the Tension of the spring will increase as well.

Thus, from this wavelength equation, an increase in velocity means an increase in tension and which will in turn mean an increase in wavelength.

Therefore, an increase in velocity propagation means a longer sinusoidal pattern.

A bird flutters around in a tree in a path described by the dark line: ​ ​ Which vector represents the average velocity of the bird? Question 2 options:

Answers

Answer:

Displacement vector represents the average velocity of the bird.

Explanation:

Given that,

A bird flutters around in a tree in a path described by the dark line.

Suppose, given vectors

(a). Time, (b). Displacement, (c). speed, (d). distance

We know that,

Vector quantity :

Vector quantity has direction and magnitude.

Average velocity :

Average velocity is equal to the displacement divided by time.

In mathematically,

[tex]v=\dfrac{D}{t}[/tex]

Where, D = displacement

t = time

We need to find the vector which is represents the average velocity of the bird

Using given data

Average velocity of the bird shows the displacement over the time.

Displacement is the vector quantity.

Hence, Displacement vector represents the average velocity of the bird.

A car originally traveling at 30.0 m/s manages to brake for 5.0 seconds while traveling 125 m along a road. After those first 5.0 seconds, the brakes fail. After an additional 5.0 seconds it travels an additional 150 m further down the road. What was the magnitude of the acceleration of the car after the brakes failed

Answers

Answer:

The magnitude of the acceleration of the car after the brakes failed is 4 m/s²

Explanation:

The car was originally traveling at 30.0 m/s, that is

The initial velocity, [tex]u[/tex] = 30.0 m/s

The time spent while the car manages to brake is 5.0 seconds, that is

time, [tex]t[/tex] = 5.0 secs

and the distance traveled during this time is

distance, [tex]s[/tex] = 125 m

From one of the equations of kinematics for linear motion,

[tex]s = ut + \frac{1}{2}at^{2} \\[/tex]

Where [tex]a[/tex] is the acceleration

We can determine the deceleration of the car during the first 5.0 seconds

Hence,

From,

[tex]s = ut + \frac{1}{2}at^{2} \\[/tex]

[tex]125 = 30.0(5.0) + \frac{1}{2}(a)(5.0)^{2}[/tex]

[tex]125 =150.0 + 12.5a[/tex]

[tex]12.5a = 125 - 150.0[/tex]

[tex]12.5a = -25\\a = \frac{-25}{12.5}\[/tex]

[tex]a = - 2.0 m/s^{2}[/tex] (Negative sign indicates deceleration)

Now we will calculate the final velocity reached at this time

From,

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

Where [tex]v[/tex] is the final velocity

[tex]v^{2} = 30.0^{2} + 2(-2.0)(125)\\v^{2} = 400\\v = \sqrt{400} \\v = 20 m/s \\[/tex]

This is the final velocity reached by the car during the first 5.0 seconds

Now, for the magnitude of the acceleration of the car after the brakes failed,

After the brakes failed,

it travels an additional 150 m further down the road, that is

s = 150m

an additional 5.0 seconds, that is

t = 5.0 seconds

Also, from

[tex]s = ut + \frac{1}{2}at^{2} \\[/tex]

The initial velocity here will be the final velocity for the first 5.0 seconds, that is,

u = 20 m/s

Hence,

[tex]s = ut + \frac{1}{2}at^{2} \\[/tex] becomes

[tex]150 = 20(5.0) + \frac{1}{2}(a)(5.0)^{2}[/tex]

[tex]150 = 100 + 12.5a\\12.5a = 150 - 100\\12.5a = 50\\a = \frac{50}{12.5} \\a = 4m/s^{2}[/tex]

Hence, the magnitude of the acceleration of the car after the brakes failed is 4 m/s²

What is the value of the radius of the following circle with an area of 154 cm2?

Answers

The area of ANY circle is (π) · (radius²).

So ...

(π) · (radius²) = 154 cm²

radius² = (154 cm²) / (π)

radius² = 49.02 cm²

radius = √(49.02 cm²)

radius = 7 cm

Answer:

[tex] \boxed{\sf Radius \ of \ circle \ (r) = 7 \ cm} [/tex]

Given:

Area of circle = 154 cm²

To Find:

Radius of circle (r)

Explanation:

[tex] \bold{Area \: of \: circle = \pi r^2}[/tex]

[tex] \sf \implies \pi {r}^{2} = 154 \\ \\ \sf \implies {r}^{2} = \frac{154}{\pi} \\ \\ \sf \implies {r}^{2} = \frac{154}{ \frac{22}{7} } \\ \\ \sf \implies {r}^{2} = \frac{154 \times 7}{22} \\ \\ \sf \implies {r}^{2} = \frac{1078}{22} \\ \\ \sf \implies {r}^{2} = 49 \\ \\ \sf \implies {r}^{2} = {7}^{2} \\ \\ \sf \implies r = \sqrt{ {7}^{2} } \\ \\ \sf \implies r = 7 \: cm[/tex]

A 1.7 kg model airplane is flying north at 12.5 m/s initially, and 25 seconds later is observed heading 30 degrees west of north at 25 m/s. What is the magnitude of the average net force on the airplane during this time interval?

Answers

Answer:

Average net force = 0.62 N

Explanation:

We are given;

Mass; m = 1.7 kg

Initial velocity; u = 12.5 m/s

Final velocity; v = 25 m/s

time; t = 25 seconds

Now, we are told that the final velocity was 30° west of North. So, resolving this velocity along the horizontal gives;

v = 25 cos 30°

Now, using Newton's first equation of motion gives;

v = u + at

Where a is acceleration

Plugging in the relevant values gives;

25 cos 30° = 12.5 + 25a

21.6506 - 12.5 = 25a

a = (21.6506 - 12.5)/25

a = 0.3660 m/s²

Now, magnitude of the average net force would be; F = ma

F = 1.7 × 0.366

F ≈ 0.62 N

imagine imagining an imagination.

Answers

i’m imagining imagining imagining an imagination...

Answer:

We’re imagining imagining imagining an imagination...

From the gravitational law, calculate the weight W (gravitational force with respect to the earth) of a 70 kg spacecraft traveling in a circular orbit 275 km above the earth's surface. Express W in Newtons and pounds.

Answers

Answer:

The  value in Newton is [tex]W =  631.92 \  N[/tex]

The  value in pounds is    [tex]W  = 142 \ lb[/tex]

Explanation:

From the question we are told that

  The  mass of the spacecraft is  [tex]m =  70 \  kg[/tex]

   The distance above  the earth is  [tex]d =  275 \  km  =  275000 \  m[/tex]

Generally the gravitational force with respect to the earth is mathematically represented as

       [tex]W =  \frac{G * m *  m_e}{ (d + r_e)^2}[/tex]

Here [tex]m_e[/tex] is the mass of earth with value [tex]m_e =  5.978 *10^{24} \  kg[/tex]

       [tex]r_e[/tex] is the radius of the earth with value  [tex]r_e  =  6371  \ km  =  6371000 \ m[/tex]

   G is the gravitational constant with value [tex]G  =  6.67 *10^{-11}  \  m^3/ kg\cdot s^2[/tex]

So

     [tex]W =  \frac{ 6.67 *10^{-11} *  70 *  5.978 *10^{24}}{ (275000 + 6371000)^2}[/tex]

     [tex]W =  631.92 \  N[/tex]

Converting to  pounds

    [tex]W =  \frac{631.92  }{4.45}[/tex]

        [tex]W  = 142 \ lb[/tex]

     

Which of the following is not a valid use of your driver's license?
O proof of your ability to operate a motor vehicle
O proof of your age
proof of your residency
O proof that you have liability insurance
NEXT QUESTION

Answers

In the state where I live, your driver's license is not a proof that you have liability insurance.  You don't need liability insurance to get a driver's license, but you need it in order to operate a car that you own.

It may be different in the state where YOU live.

NEXT QUESTION

Write all the different ways you can think of that describe what it means to be healthy

Answers

Answer:

Eat more healthy foods.  Workout and build your immune system.

Explanation:

Eat  Healthy foods like Carrots, Apples, Bannas, Pears, and anything that deals with not much of any sugar. An example of unhealthy foods is Cakes, Chocolates, Candy, and more. Drink a lot of water.

A sidewalk has a length of 75.00m. How many inches is this? (Hint: you need to use two unit conversion fraction. 1 cm equals about 0.3937 inches)

Answers

Length = (75.00 m)

Length = (75 meter) x (3.28084 foot/meter) x (12 inch/foot)

Length = (75 x 3.28084 x 12) (meter-foot-inch / meter-foot)

Length = 2,952.76 inches

The main force(s) acting on the puck after receiving the kick is (are):_________.A) a downward force of gravity and an upward force exerted by the surfaceB) a downward force of gravity, and a horizontal force in the direction of motionC) a downward force of gravity, an upward force exerted by the surface, and a horizontal force in the direction of motionD) a downward force of gravityA) a downward force of gravity and an upward force exerted by the surface

Answers

Answer:

the statements, the correct one is A

a downward force of gravity and an upward force exerted by the surface

Explanation:

When the disc is hit, a thrust force is exerted in the direction of movement, at the moment the disc moves this force loses contact and becomes zero.

When the movement is already established there are two main forces: gravity that acts downwards and the reaction force to the support of the disk called normal that acts upwards.

As it is not mentioned that there is friction, this force that opposes the movement is zero.

Analyzing the statements, the correct one is A

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