Which describes the role of the muscular system during physical activity?
Select all that apply.
1: It allows for movement.
2: It controls the breathing rate.
3: It forces venous blood to return to the heart.
4: It controls the heart rate.

Explanation:

the electrostatic force is also known as the coulomb force or coulomb interaction. it's the attractive or repulsive force between two electrically charged object. like charges repel each other while unlike charges attract each other. coulomb's law is used to calculate the strength of the force between two charger .

Answer:

3 secods later

Explanation:

Answer:

C. Try an element in the same group as lithium.

Explanation:

Answer:

The answer is C.

Explanation:

I'm took the test on it

Answer: it is located over Ellesmere Island, Canada

Explanation

it is now drifting away from North America and toward Siberia.

Answer:ellesmere island, Canada

Answer:

[tex]\Delta L = 300\,m[/tex]

Explanation:

La longitud del tren se deriva de la siguiente fórmula (The length of the train is derived from the following formula):

[tex]\Delta L + 200\,m = v\cdot \Delta t[/tex]

[tex]\Delta L = \left(36\,\frac{km}{h} \right)\cdot \left(1000\,\frac{m}{km} \right)\cdot \left(\frac{1}{3600}\,\frac{h}{s} \right)\cdot (50\,s) - 200\,m[/tex]

La longitud del tren es (The length of the train is):

[tex]\Delta L = 300\,m[/tex]

Answer:

51.02m

Explanation:

KE = 1/2mv2

Where k.e = 250J

mass = 0.5 kg

g = 9.8 m/s2

250= 1/2×0.5×v^2

250= 0.5×0.5×v^2

250= 0.25v^2

v^2 = 250/0.25

v^2 = 1000

v =√1000

v = 31.62m/s

v^2= u^2-2gh........... (1)

Since the object will stop at it highest point, hence it final velocity there will be zero and since it is moving up against the gravity g= -9.8m/s^2. That was why the formula in equation 1 has a negative sign

From h = u^2/2g

Where v = 31.62m/s

g = 9.8m/s^2

H = (31.62m/s)^2/9.8×2

H= 1000/19.6

= 51.02m

Hence the height of it travelling will be

51.02m

Answer: there are 15 coins of $2 and 18 coins of $5

Explanation:

I will answer in English.

X is the number of $5 coins.

Y is the number of $2 coins.

We have the system of equations:

Y + X = 33

Y*2 + X*5 = 120

first, we must isolate one of the variables in one of the equations and then replace it in the other equation, let's isolate Y in the first equation:

Y = 33 - X.

Then we can replace it in the other equation:

(33 - X)*2 + X*5 = 120

66 - X*2 + X*5 = 120

X*3 = 54

X = 54/3 = 18

and using the equation for Y.

Y = 33 - X = 33 - 18 = 15

So there are 15 coins of $2 and 18 coins of $5

Answer:

gamma waves

Explanation:

gamma rays" from lightning discharges at 10 to 20 MeV, and known to be produced by the bremsstrahlung mechanism. Another example is gamma-ray bursts, now known to be produced from processes too powerful to involve simple collections of atoms undergoing radioactive decay.

Answer:

Explanation:

This problem indicates that the speed of light in a material medium is 0.5 10⁸ m / s, they ask to find the critical angle between the material and the vacuum

Let's find the refractive index of the material

            n = c / v

           n = 3 10⁸ / 0.5 10⁸

           n = 6

When the material passes from one medium to another, it must comply with the law of refraction

           n₁ sin θ = n₂ sin θ₂

for the angle criticize the angles tea2 = 90

          tea = sin⁻¹n₂/ n₁

The vacuum replacement index is n₂ = 1

         tea = sin⁻¹ (1/6)

         tea = 9.59º

Answer:

30 degrees

Explanation: First, what is the critical angle? Critical angle is the angle from the normal, at which light enters another medium, which causes the reflected light to reflect at an angle of 90 degrees.

Using Snell's Law:

critical angle = sin^-1(n2/n1)

n2 = c/v. In a vacuum this = 1

n1 = c/.5c = 2

critical angle = sin^-1(1/2)=30 degrees

Answer:

because it is due the Intrecation between sub atomic particles

Answer:

33.23 m

Explanation:

At the point where both objects will meet, the vertical height will be equal.

From the equations of motion, the vertical height of the body falling at any time is given as

(y - y₀) = ut + ½gt²

y = vertical height at any time T

y₀ = initial height of the object = 81.5 m

u = initial velocity = 0 m/s (body was dropped)

g = -9.8 m/s²

(y - 81.5) = 0 - 4.9T²

y = 81.5 - 4.9T² (eqn 1)

For an object thrown up, the vertical height of the body at any time, t, is given as

(y - y₀) = ut + ½gt²

y = vertical height of the object at any time t

y₀ = initial height of the object = 0 m

u = initial velocity = 40 m/s

g = -9.8 m/s²

y = 40t - 4.9t² (eqn 2)

At the point where the two objects meet, we equate eqn 1 and eqn 2

y = y

81.5 - 4.9T² = 40t - 4.9t²

But T = (t + 2.2) (Since object 2 was dropped 2.2 s after object 1)

81.5 - 4.9(t + 2.2)² = 40t - 4.9t²

81.5 - 4.9(t² + 4.4t + 4.84) = 40t - 4.9t²

81.5 - 4.9t² - 21.56t - 23.716 = 40t - 4.9t²

81.5 - 21.56t - 23.716 - 40t = 0

57.784 = 61.56t

t = (57.784/61.56) = 0.93866 = 0.94 s

Therefore, the vertical height at t = 0.93866 s is

y = (40×0.93866) - 4.9(0.93866²) = 33.23 m

Hope this Helps!!!

Answer:

The generator will work only if the magnetic field associated with the turns of coil change.

here both magnet and coil are stationary with respect to each other so no electromagnetic induction would take place. so no indiced current will be produced.

the student has to introduce some mechanism either to rotate the coil or the magnet

Answer:

Explanation:

Given data

[tex]speed= 40.23m/s\\[/tex]

[tex]time[/tex] =[tex]0.70second[/tex]

To determine the deceleration  we apply,

[tex]acceleration = \frac{speed}{time} \\\\acceleration= \frac{40.23}{0.7}[/tex]

[tex]acceleration = -57.47m/s^{2}[/tex]

Answer:

(1) V = 0.2 J (2) 0.05J

Explanation:

Solution

Given that:

K = 160 N/m

x = 0.05 m

Now,

(1) we solve for the  initial potential energy stored

Thus,

V = 1/2 kx² = 0.5 * 160 * (0.05)²

Therefore V = 0.2 J

(2)Now, we solve for how much of the internal energy is produced as the toy springs up to its maximum height.

By using the energy conversion, we have the following

ΔV = mgh

=(0.1/9.8) * 9.8 * 1.5 = 0.15J

The internal energy = 0.2 -0.15

=0.05J

Answer:

1.125 m/s²

Explanation:

Applying Newton's equation of motion,

v² = u²+2as

Where v = final velocity, u = initial velocity, a = acceleration, s = distance.

Note: u = 0 m/s ( from rest)

make a the subject of the equation above.

a = v²/2s................ Equation 2

Given: v = 15 m/s². s =  100 m

Substitute into equation 2

a = 15²/(2×100)

a = 225/200

a = 1.125 m/s²

The magnitude of the car's acceleration is 1.125 m/s²

The calculation can be as follows;

u= 0

v= 15m/s

s= 100 meters

The formular is

v²= u² + 2as

15² = 0² + 2(a)(100)

225= 200a

a= 225/200

a= 1.125

Hence the initial velocity is 1.125 m/s²

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https://brainly.com/question/6078363?referrer=searchResults

Answer:

It's the duration between successive new moons. Also called a lunation or synodic month, it has a mean period of 29.53059 days (29 days 12 hours and 44 minutes).

Answer: seen below

Explanation:

a) Water has the highest specific heat capacity in this case while sand has the lowest specific heat capacity.

b) Sand absorb the least energy for it temperature change (increase or decrease). This means that their temperatures change more quickly due to it low specific heat capacity of 0.290J/g°C) at 25°C)

c) using the formula:

Q = m × cP × (final temperature -initial temperature)

where:

Q = heat

m = is the mass

cP = is the mass heat capacity,

T= is the temperature

Q = 2 kg × 600 J/(kg°C) × (30°C - 20°C)

Q = 12000 J

d) in simpler term, The second law of thermodynamics states that when energy changes from one form to another form, entropy The second law of thermodynamics says that when energy changes from one form to another form, or matter moves freely, entropy (which is a measure of the amount of energy in a physical system that cannot be used to do work) in a closed system increases. This is why your feet gets cold when you put them in the water.

Answer:

x_total = 20m

Explanation:

This is an exercise in kinematics, we will look for the distance it travels during the reaction time, where there is no braking, and then the distance during the deceleration.

Distance traveled during response time

           v = x₁ / t

           x₁ = v t

let's calculate

          x₁ = 10 0.75

          x₁ = 7.5 m

Now we calculate the distance during braking, the final speed is zero (v = 0)

         v² = v₀² - 2 a x₂

         x₂ = v₀² / 2 a

let's calculate

         x₂ = 10² / (2 4)

         x₂ = 12.5m

the total stopping distance is

        x_total = x₁ + x₂

        X_total = 7.5 + 12.5

        x_total = 20m

Answer:

A larger force than 70 N will be required for the box to continue moving

Explanation:

A ramp is an inclined plane surface that is tilted to form a slope on its opposite sides

A ramp provides mechanical advantage or force amplification, by allowing less force to lift heavier load from having to move through a longer distance to reach a particular elevation when the slope of the ramp is gentle

Therefore, when the slope is steeper, and shorter, more force than 70 N will be required for the box to continue moving.

Answer:  

your force needs to increase to more than 70 N

Explanation:

plato

Answer:

if we drop it and not throw it then

after 0.75 how fast the book is falling is given by its velocity as

v= at

= 9.8 × 0.75

=7.35 m/s

Answer:

speed = 40 m/s

Explanation:

speed = frequency x wavelength

speed = 10 Hz x 4 m

speed = 40 m/s

Answer:

If the speed is 70 mile/hour, the time to drive the 256 miles is:

T = 256/70 = 3.66 hours = 3 hours and 39.6 minutes

If you leave at 3:00, then at 6 hours and 39.6 minutes, you will get there.

Hope this helps!

:)

Answer:

a)  y = 42 t - 4,905 t² ,      v = 42 - 9.81 t,  b)   t = 4.281 s , c)   y = 89.9 m

Explanation:

This problem is an example of vertical launch

a) the expression for the position is

         y = v₀ t - ½ g t²

we substitute

          y = 42 t - 4,905 t²

the expression for speed is

        v = v₀ - gt

        v = 42 - 9.81 t

b) the speed is null when v = 0

         v₀ = gt

          t = v₀ / g

          t = 42 / 9.81

          t = 4.281 s

c) for the maximum height we can use the expression

        v² = v₀² - 2gy

    at maximum height v = 0

         y = v₀² / 2g

     let's calculate

        y = 42 2/2 9.81

        y = 89.9 m

Answer:

As voltage increases, current increases and resistance stays the same .

Explanation:

Ohm's law gives the relationship between the voltage, resistance, and current. The mathematical form of Ohm's law is given by :

[tex]V\propto I\\\\V=IR[/tex]

R is resistance

I is current

V is voltage

So, as voltage increases, current increases and resistance stays the same. The correct option is (A).

Answer:

a. 165.5 V

b. 7.78 A

Explanation:

Here is the complete question

The RMS potential difference of an AC household outlet is 117 V. a) What is the maximum potential difference across a lamp connected to the outlet? b) If the RMS current through the lamp is 5.5 A, what is the maximun current through the lamp.

Solution

a. The maximum potential difference across the lamp V₀ = √2V₁ where V₁ = rms value of potential difference = 117 V

V₀ = √2V₁ = √2 × 117 V = 165.5 V

b. The maximum current through the lamp I₀ = √2I₁ where I₁ = rms value of current = 5.5 A

V₀ = √2V₁ = √2 × 5.5 A = 7.78 A

Answer:

Explanation:

the victims cell phone