what was the average speed in km/h of a car that travels 490.0 km in 4.2 h?

Answer:

Explanation:

Given the the path of an object at a 45° with initial velocity of 80 feet per second modeled by the equation [tex]h(x) = (-\dfrac{32}{80^2} )x^2 + x[/tex] where;

x is the horizontal distance traveled and h(x) is the height in feet, if x is given as 100 ft, the height of the object will be gotten by simply substituting x = 100 into the modeled function as shown;

[tex]h(x) = (-\dfrac{32}{80^2} )x^2 + x\\\\h(100) = (-\dfrac{32}{80^2} )100^2 + 100\\\\h(100) = (-0.005 )100^2 + 100\\\\h(100) = (-0.005 )10,000 + 100\\\\h(100) = -50 + 100\\\\h(100) =50 feet[/tex]

Hence height of the object when it has traveled 100 feet away horizontally is 50 feet.

Answer:

v = 100 m/s

Explanation:

Given:

v₀ = 0 m/s

a = 10 m/s²

t = 10 s

Find: v

v = at + v₀

v = (10 m/s²) (10 s) + 0 m/s

v = 100 m/s

Answer:

A. 23.9

B.22.9

C. The levels will be equal

D. Obviously that will be to maintain atmospheric pressure

Explanation:

For mercury the pressure in both tubes at R is same so

P_left = P_right

Thus

=>>>Po + rho_t x g x (5 + R - 1.5) = Po + rho_ m x g x R

rho_t x g x (5 + R - 1.5) = rho_m x g xR

rho_t x (3.5 + R) = rho_m x R

3.5 + R = (rho_m/rho_t) x R

3.5 + R = (13560/867) x R

3.5 + R = 15.64 x R

R x (15.64 - 1) = 3.5

R = 3.5/14.64

= 0.239 m

= 23.9 cm  this is for Mercury

ii)water

similarly,

3.5 + R = (rho_w/rho_t) x R

3.5 + R = (1000/867) x R

3.5 + R = 1.153 x R

R X (1.153 - 1) = 3.5

R = 3.5/0.153

= 22.9m for water

Answer: I believe farther. Correct me if I am wrong

Explanation:

Answer:

Closer.

Explanation:

Due to the refraction of light passing through water and air.

Answer:

The slower runner is 1.71 km from the finish line when the fastest runner finishes the race.

Explanation:

Given;

the speed of the slower runner, u₁ = 11.8 km/hr

the speed of the fastest runner, u₂ = 15 km/hr

distance, d = 8 km

The time when the fastest runner finishes the race is given by;

[tex]Time = \frac{Distance }{speed}\\\\Time = \frac{8}{15} \\\\Time = 0.533 \ hr[/tex]

The distance covered by the slower runner at this time is given by;

d₁ = u₁ x 0.533 hr

d₁ = 11.8 km/hr x 0.533 hr

d₁ = 6.29 km

Additional distance (x) the slower runner need to finish is given by;

6.29 km + x = 8km

x = 8 k m - 6.29 km

x = 1.71 km

Therefore, the slower runner is 1.71 km from the finish line when the fastest runner finishes the race.

Answer:

The smallest possibility is 0.01E-22kgm/s

Explanation:

Using

Momentum= h/4πx

= 6.6x 10^-34Js/ 4(3.142* 50*10-12m)

= 0.01*10^-22kgm/s

Answer:

The  value is  [tex]\theta_2 = 20.322^o[/tex]

Explanation:

From the question we are told that

  The angle of the first order maximum is  [tex]\theta _1 = 10.0^o[/tex]

Generally the condition for constructive interference is  

     [tex]dsin\theta = n \lambda[/tex]

Here  d is the separation between the slit ,

n  is the order of maxima  with values n  =  1, 2 , 3 ... for first , second , third ... order of maxima

    Now for first order of maximum

        [tex]dsin\theta_1 = \lambda \ \ ... \ \ ( 1)[/tex]

=>      [tex]dsin(10) = \lambda \ \ ... \ \ ( 1)[/tex]

    Now for second order of maximum

       [tex]dsin\theta = 2\lambda \ \ ... \ \ ( 2)[/tex]

dividing equation 1  by 2

      [tex]\frac{d sin (10)}{d sin (\theta_2 )} = \frac{\lambda}{2\lambda}[/tex]

     [tex]\frac{ sin (10)}{ sin (\theta_2 )} = \frac{1}{2}[/tex]

=>   [tex]2sin(10) = sin (\theta_2 )[/tex]

=>    [tex]0.3473 = sin(\theta_2)[/tex]

=>   [tex]\theta_2 = sin^{-1} [0.3473][/tex]

=>   [tex]\theta_2 = 20.322^o[/tex]

Explanation:

It is given that,

Power of EM waves, P = 1800 W

We need to find the intensity at a distance of 5 m. Also, the rms value of the electric field.

Intensity,

[tex]I=\dfrac{P}{4\pi r^2}\\\\I=\dfrac{1800}{4\pi\times (5)^2}\\\\I=5.72\ W/m^2[/tex]

The formula that is used to find the rms value of the electric field is as follows :

[tex]I=\epsilon_o cE^2_{rms}[/tex]

c is speed of light and [tex]\epsilon_o[/tex] is permittivity of free space

So,

[tex]E_{rms}=\sqrt{\dfrac{I}{\epsilon_o c}}\\\\E_{rms}=\sqrt{\dfrac{5.72}{8.85\times 10^{-12}\times 3\times 10^8}}\\\\E_{rms}=46.41\ V/m[/tex]

Hence, this is the required solution.

Answer:

The final velocity of the object after 2 seconds is 30 m/s

Explanation:

Given;

constant downward acceleration, a =  10 m/s²

initial velocity of the object falling down, v = 10 m/s

time of fall, t = 2 s

The final velocity of the object is given by;

v = u + at

where;

v is the final velocity

v = 10 + (10)(2)

v = 10 + 20

v = 30 m/s

Therefore, the final velocity of the object after 2 seconds is 30 m/s

Complete Question

A circular area with a radius of 6.60 cm lies in the xy-plane. What is the magnitude of the magnetic flux through this circle due to a uniform magnetic field B = 0.250 T oriented in the following ways?

(a) in the +z-direction

Wb

(b) at an angle of 54

Answer:

a

[tex]\phi = 0.00342 \ Wb[/tex]

b

[tex]\phi = 0.00201 \ Wb[/tex]

Explanation:

From the question we are told that

   The  radius is  [tex]r = 6.60 \ cm = 0.066 \ m[/tex]

    The magnitude of the magnetic field is [tex]B = 0.250 \ T[/tex]

Generally the cross -sectional area is mathematically represented as

     [tex]A = \pi r^2[/tex]

     [tex]A = 3.142 * (0.066)^2[/tex]

     [tex]A = 0.01369 \ m^2[/tex]

Generally  when the magnetic field is oriented in the +z-direction the magnetic flux is mathematically represented as

      [tex]\phi = B* A cos(0)[/tex]

=>    [tex]\phi = 0.01369 * 0.250 * cos (0)[/tex]

=>     [tex]\phi = 0.00342 \ Wb[/tex]

  Now when the magnetic field is oriented  at an angle of 54°  the magnetic flux is mathematically represented as

      [tex]\phi = B* A cos(54)[/tex]

      [tex]\phi = 0.01369 * 0.250 * cos (54)[/tex]

     [tex]\phi = 0.00201 \ Wb[/tex]

Answer:

26 lbft

Explanation:

Given that

Force exerted by the woman, F = 5 lb

Length of the ramp, d = 6 ft

angle of inclination, θ = 30° above the horizontal

Work done on the box, W = ?

This is very much a straightforward question..

Work done, W = F * d, where the force takes the factor of the Angie if inclination. So that,

W = Fcosθ * d

On substituting, we have

W = 5 * cos 30 * 6

W = 5 * 0.866 * 6

W = 30 * 0.866

W = 25.98 lbft

Therefore, the work done on the box is 25.98 or approximately 26 lbft

Answer:

1.8*10^8m/s

Explanation:

Using

L= lo√1-v²/c²

So making v subject we have

V= c√1-4.8²/6²

V= 0.6*c

V= 0.6*3E8m/s

V= 1.8*10^8m/s

Answer:

A) J= 398 A/m²

B) E= 1.6×10⁶ N/C

C) P= ×10⁴ W

Explanation:

My work is in the attachment. Comment with questions or if something seems wrong with my work. (Honestly, they seem little high but it could just be the given numbers being unrealistic.) Below I have explanations of each part to match up with the image as well.

Part A:

Current density (J) is defined as the amount of current in a particular cross-sectional area. To get this, we simply need to divide the current (I) by the cross-sectional area of the electron beam tube (A).

Part B:

This one took the most work for me. I used a kinematic equation (yes they apply to electrons) to find the electric field (E). I used a modified form of the familiar: ∆d=V₀τ+aτ²/2

We can use the fact that τ= V/a, a=(qE/m), and V₀=0 here to rewrite the equation in terms of values we know and/or can look up. From there we solve for E and plug in the values.

Part C:

Power (P) is simply work (W) over time (τ). We know what τ is from before and can take W= mV²/2. Plugging these in and reducing some values gives us an equation for power as well.

Answer:

The distance of the cat will appear farther than it really is

Explanation:

The index of refraction of water is more than that of air. Light rays from the cat  are refracted towards the normal at the surface and diverge outwards. This extends the virtual position of the cat, putting in a place farther than it really is.

Complete question:

a farmer wants to use a wireless camera he has installed in his barn which is about 100 yards from his house. what kind of antenna should he use on the house and barn to get the best signal.

Answer: Unidirectional antenna

Explanation: Based on the description given in the scenario above, the farmer should use a unidirectional antenna in other to get the best signal taking advantage of the fact that he knows where he wants the Transmission to come from. The good transmission signal attributed to unidirectional antennas stems from the fact that, the area covered is relatively small as signal transmission and radiofrequecy energy is focused in a particular direction, meaning that less area is covered using a unidirectional antenna,hiwevwr, it leverages this limitation to provide very good signal within the limited area covered.

Answer:

E = 134.85 N/C

Explanation:

We are given;

Electric field location; b = <-0.2, -0.4, 0> m

Charge: q = 3 nc = 3 × 10^(-9) C

From the location given, we have total distance;

r = √((-0.2²) + (-0.4)² + (0²))

r = √0.2

Formula for Electric field is;

E = kq/r²

where;

k is a constant with a value of 8.99 x 10^(9) N.m²/C²

q is charge on the proton particle with a costant value = 1.6 × 10^(-19) C

r is the distance

Plugging in the relevant values, we have;

E = (8.99 x 10^(9) × 3 × 10^(-9))/(√0.2)²

E = 134.85 N/C

Find out more information about  <-0.2, -0.4, 0> here:

https://brainly.com/question/13309193

Answer:

The time taken in years is   [tex]x = 125 \  years[/tex]

Explanation:

From the question we are told that

   The  speed is  [tex]v  = 540.00 \ km /hr  =  \frac{540 *1000}{3600} =  150\  m/s[/tex]

    The distance from the sun to Pluto is  [tex]d =  5.9*10^{9} \  k m =  5.9*10^9 * 1000 =  5.9*10^{12} \  m[/tex]

Generally the time  taken is mathematically represented as

     [tex]t =  \frac{d}{v}[/tex]

=>   [tex]t = \frac{5.9*10^{11}}{150}[/tex]

=>   [tex]t =  3.933*10^{9}[/tex]

Converting to years

   [tex]1 year  \to  3.154*10^7 \  s[/tex]

    [tex]x \  years  \to 3.933*10^{9}[/tex]

=>  [tex]x = \frac{ 3.933*10^{9} * 1 }{ 3.154 *10^7}[/tex]

=>    [tex]x = 125 \  years[/tex]

Explanation:

Heat is a form of energy that can transfer from hot body to cold body.Temperature is the degree of hotness and coldness of a body.

Heat is measured in joules, but temp. is measured in Kelvin

Answer:

temperature is the degree of hotness and coldness of the body or an object while heat is the energy transferred from hot to a cooler object as a result if differencein temperature ☺

Answer:

The wavelength in nanometers is 849.81 nanometers (nm)

Explanation:

Here is the complete question:

A laser technician measures the wavelength of light from a new semiconductor laser. The wavelength is 8.4981 × 10⁻⁷m . What is the wavelength in nanometers. Write your answer as a decimal.

Explanation:

The given wavelength is 8.4981 × 10⁻⁷m.

To determine the wavelength in nanometers, we will convert the given wavelength from meters (m) to nanometers (nm).

1 nanometer = 1 × 10⁻⁹ meters

∴ 10⁻⁹ meters = 1 nanometer

To convert 8.4981 × 10⁻⁷m to nanometer (nm):

If 10⁻⁹ meters (m) = 1 nanometer (nm)

Then,  8.4981 × 10⁻⁷m = (8.4981 × 10⁻⁷m × 1 nm) / 10⁻⁹ m

8.4981 × 10⁻⁷m = 8.4981 × 10⁻⁷ × 10⁹ nm

= 8.4981 × 10² nm

= 849.81 nm

Hence, the wavelength in nanometers is 849.81 nm

The nuclear force is a force that acts between the protons and neutrons of atoms.

The nuclear force is a force that binds the protons and neutrons in a nucleus together.This force can exist between protons and protons,neutrons and protons and neutrons and neutrons.This force is what hold the nucleus together.

Answer:

"the magnitude of the magnetic field at a point of distance a around a wire, carrying a constant current I, is inversely proportional to the distance a of the wire from that point"

Explanation:

The magnitude of the magnetic field from a long straight wire (A approximately a finite length of wire at least for close points around the wire.) decreases with distance from the wire. It does not follow the inverse square rule as is the electric field from a point charge. We can then say that "the magnitude of the magnetic field at a point of distance a around a wire, carrying a constant current I, is inversely proportional to the distance a of the wire from that point"

From the Biot-Savart rule,

B = μI/2πR

where B is the magnitude of the magnetic field

I is the current through the wire

μ is the permeability of free space or vacuum

R is the distance between the point and the wire, in this case is = a

Answer:

35.11 m/s

Explanation:

While flying due east at 33 meters/second, an airplane is also being carried due north at 12 meters/second by the wind, then the plane’s resultant velocity would be 35.11 meters/second.

The total displacement covered by any object per unit of time is known as velocity.

the mathematical expression for velocity is given by

velocity = total displacement /total time

As given in the problem , while flying due east at 33 m/s, an airplane is also being carried due north at 12 m/s by the wind and we have to find the resultant velocity of the plane,

Resultant velocity = √( 33² + 12²)

                              = 35.11 meters/second

Thus, the plane’s resultant velocity would be 35.11 meters/second

Learn more about Velocity here, refer to the link;

brainly.com/question/18084516

#SPJ2

Answer:

The mmf required is [tex]1.125[/tex]×[tex]10^{-3}[/tex] A

Explanation:

The Magnetomotive force (mmf) is given by the formula below

[tex]F_{M} = Hl\\[/tex]

where [tex]F_{M}[/tex] is the Magnetomotive force (mmf)

[tex]H[/tex] is the Magnetic field strength

[tex]l[/tex] is the magnetic length

The magnetic permeability μ is given by

μ = [tex]B / H[/tex]

Where [tex]B[/tex] is the Magnetic flux density

and [tex]H[/tex] is the Magnetic field strength

From the question,

[tex]B[/tex] = 1.2Wb/m^2

μ = 1600m

From μ = [tex]B / H[/tex]

∴[tex]H = B/[/tex]μ

[tex]H = 1.2 / 1600\\[/tex]

[tex]H = 7.5[/tex] × [tex]10^{-4}[/tex]A/m

Now, for the Magnetomotive force (mmf)

[tex]F_{M} = Hl\\[/tex]

From the question

[tex]l[/tex] = 1.5 m

∴ [tex]F_{M} = 7.5[/tex]×[tex]10^{-4}[/tex] × [tex]1.5[/tex]

[tex]F_{M} = 1.125[/tex]×[tex]10^{-3} A[/tex]

Hence, The mmf required is [tex]1.125[/tex]×[tex]10^{-3}[/tex] A

Answer:

v = rw

Explanation:

When an object is rolling continuously without slipping, then every angle it rotates through, is equal to a distance the perimeter has rotated.

If the object completes 10 revolutions and takes a particular time, let's say t to complete it. The angular distance would then be 20 π rad, while its angular velocity will be 20 π/t

The circumference will somehow translate to the distance it covers, which is 20πr, this means that the speed is 20πr/t

So, like the question asked, the linear speed compared to angular speed is

v : w

20πr/t : 20πt, which can be simplified to

r : 1

In essence, v = rw

Answer:

This is due to variation bin air pressure at the two different altitudes, so air rushes out through the eustachian tube to hit the eardrum and back when u reach the ground

Answer:

the magnetic field must go in a direction parallel to the page perpendicular to the current.

Explanation:

The Hall effect is the voltage produced by the movement of electrons due to the effect of electric and magnetic fields in a material

            F = eE + v x B

The electric field goes in the direction of the current that is opposite to the direction of the electrons, therefore the magnetic force must be perpendicular to it.

Therefore, if the current goes in a direction parallel to the page, in the x direction, the magnetic field must be perpendicular to it if we use the rule of the right wizard,

thumb points in the direction of E, x axis parallel page

The fingers extended should go parallel to the page in the direction and up

The palm is the direction of the Force, where the voltage will be produced points out the page, this is for positive charges, as in germanium the charges are negative, the real force goes into the page.

Therefore the electrons accumulate on the inside of the page and the voltage is negative in this part.

Therefore the voltage is positive on the outside of the sheet. In conclusion the magnetic field must go in a direction parallel to the page perpendicular to the current.

Answer:

The value  is   [tex]S =  7.96[/tex]

Explanation:

From the question we are told that

       The  power is  [tex]P =  100 \  W[/tex]

       The radius  is  [tex]r =  1 \  m[/tex]

Generally the average value of the magnitude of the Poynting vector is mathematically represented

          [tex]S  =  \frac{P}{4 \pi r^2}[/tex]

   =>    [tex]S =  \frac{ 100 }{ 4 *3.142 *1^2 }[/tex]

  =>     [tex]S =  7.96[/tex]

Answer:

b. 0.493

Explanation:

Answer:

52°

Explanation:

The initial intensity [tex]I_{0}[/tex] = [tex]I[/tex]

The final intensity [tex]I_{f}[/tex] = 38% of [tex]I[/tex] = 0.38

From the polarizing equation

[tex]I_{f} = I_{0} cos^{2}[/tex]θ

substituting values, we have

[tex]0.38I = I cos^{2}[/tex]θ

0.38 = [tex]cos^2[/tex]θ

cosθ = [tex]\sqrt{0.38}[/tex]

cosθ = 0.6164

θ = [tex]cos^{-1}[/tex] 0.6164

θ = 51.9 ≅ 52°

Answer:

D. 10 seconds

Explanation:

All Houston Methodist Hospital buildings employs the use of EPSS(Emergency Power Supply System). This system employs the use of an emergency power generator that turns on to supply emergency power after normal power shuts down within 10 seconds during power outage.

Due to it being used in a hospital the importance of this emergency power system cannot be overemphasized as it is used to provide power supply to hospital equipment such as life support machines etc.