At 2:00, Alice was traveling in a car at 40 miles/hour. She then slows down, and at 4:00, she was traveling at 20 miles/hour.


What was Alice’s average acceleration between 2:00 and 4:00?
Show your complete calculation and state your answer with the correct units.

a particle of violet light has exactly the same energy as a particle of red light

Answer:

the number of electrons should equal to the the number of protons in a neutral atom

if there is a inequality between the numbers it means the atom has a + or - charge

Answer:

Explanation:

For time period of revolution , the expression is as follows .

T² =  4π² R³ /GM , M is mass of the earth.

Putting the values

T² =  4π² (7880 x 10³)³ /(6.67 x 10⁻¹¹ )( 5.97 x 10²⁴ )

T² = 4.846 x 10⁷ s

T = 6.961 x 10³ s

= 6961 s

= 116 minutes .

Answer:

To increase the conductivity of the material.

Explanation:

Generally , the group 4 elements are non conductor but in certain conditions, such as doping or the increase in temperature, they becomes conductor.

The doping is the process of mixing of pentavalent or the trivalent material into tetra valent material in the very small amount, so that the material becomes conductor.

In making a diode we need two types of the materials, n type semiconductor and p type semi conductor.

When the trivalent impurity is added in the tetra valent element, the semiconductor becomes n type because an electron is left for the conduction.

When the pentavalent impurity is added in the tetra valent element, the semiconductor becomes p type because a hole is left for the conduction.

Answer:

I think the particles transferred between brandi's body and the door knob causing the shock is the electrons.

Answer: hello your question is incomplete attached below is the complete question

answer :  1/2 KD^2  ( option A )

Explanation:

P.E ( potential energy ) = mgd

In case 1 P.E = 0   i.e. mgd = 0  

Given that in case 2 the Mass M had moved through the Distance D by the compression of the spring

The potential energy of the M in case 2

= P.E of M at rest + P.E of the spring

= 0 + 1/2 KD^2

Answer:

We cannot tell from the information given

Explanation:

Given;

mass of the box, m = 5 kg

first force, F₁ = 10 N

second force, F₂ = 5 N

(I) Assuming the two forces are acting horizontally in opposite direction, the resultant force on the box is calculated as;

∑Fx = 10 N - 5 N

      = 5 N

Apply Newton's second law of motion;

∑Fx = ma

a = ∑Fx/m

a = 5 / 5

a = 1 m/s² in the direction of the 10 N force.

(II) Also, if the two forces are acting in the same direction, the resultant force is calculated as;

∑Fx = 10 N + 5 N

∑Fx = 15 N

a = 15 / 5

a = 3 m/s²

Therefore, the information given is not enough to determine the acceleration of the box.

Answer:

39.40 MeV

Explanation:

Determine the minimum possible Kinetic energy

width of region = 5 fm

From Heisenberg's uncertainty relation below

ΔxΔp ≥ h/2 , where : 2Δx = 5fm ,  Δpc = hc/2Δx = 39.4 MeV

when we apply this values using the relativistic energy-momentum relation

E^2 = ( mc^2)^2 + ( pc )^2 = 39.4 MeV ( right answer ) because the energy grows quadratically in nonrelativistic approximation,

Also in a nuclear confinement ( E, P >> mc )

while The large value will portray a Non-relativistic limit  as calculated below

K = h^2 / 2ma^2 = 1.52 GeV

Answer:

The answer is " because it is in the opposite direction of the bullet".

Explanation:

Given:

[tex]m_1= 70 \ kg\\\\m_2 = 0.01\ kg\\\\v_2 = 500\ \frac{m}{s}\\\\v_1 = ?[/tex]

Using formula:

It recoils the velocity of the rifle [tex]= -0.07142 \ \ \frac{m}{s}[/tex]  

Its negative sign displays the opposite direction of the rifle.

Answer: 321 J

Explanation:

Given

Mass of the box [tex]m=3\ kg[/tex]

Force applied is [tex]F=25\ N[/tex]

Displacement of the box is [tex]s=15\ m[/tex]

Velocity acquired by the box is [tex]v=6\ m/s[/tex]

acceleration associated with it is [tex]a=\dfrac{F}{m}[/tex]

[tex]\Rightarrow a=\dfrac{25}{3}\ m/s^2[/tex]

Work done by force is [tex]W=F\cdot s[/tex]

[tex]W=25\times 15\\W=375\ J[/tex]

change in kinetic energy is [tex]\Delta K[/tex]

[tex]\Rightarrow \Delta K=\dfrac{1}{2}m(v^2-0)\\\\\Rightarrow \Delta K=\dfrac{1}{2}\times 3\times 6^2\\\\\Rightarrow \Delta K=\dfrac{1}{2}\times 3\times 36\\\\\Rightarrow \Delta K=54\ J[/tex]

According to work-energy theorem, work done by all the forces is equal to the change in the kinetic energy

[tex]\Rightarrow W+W_f=\Delta K\quad [W_f=\text{Work done by friction}]\\\\\Rightarrow 375+W_f=54\\\Rightarrow W_f=-321\ J[/tex]

Therefore, the magnitude of work done by friction is [tex]321\ J[/tex]

Answer:

The speed will be "0.144 rad/s".

Explanation:

Given that,

Diameter,

d = 7.50 km

Radius,

R = [tex]\frac{7.5}{2} \ Km[/tex]

Acceleration on inner curve,

= 8 times

Now,

As we know,

⇒ [tex]\omega^2R=8g[/tex]

or,

⇒ [tex]\omega=\sqrt{\frac{8g}{R} }[/tex]

On substituting the values, we get

⇒     [tex]=\sqrt{\frac{8\times 9.8}{\frac{7.5}{2}\times 10^3 } }[/tex]

⇒     [tex]=\sqrt{\frac{78.4}{3750} }[/tex]

⇒     [tex]=\sqrt{0.0209}[/tex]

⇒     [tex]=0.144 \ rad/s[/tex]

Answer:

Golgi apparatus (bodies).

Explanation:

A cell can be defined as the fundamental or basic functional, structural and smallest unit of life for all living organisms. Some living organisms are unicellular while others are multicellular in nature.

Generally, cells have the ability to independently replicate themselves. In a cell, the "workers" that perform various functions or tasks for the survival of the living organism are referred to as organelles. Some examples of cell organelles found in all living organisms such as trees, birds, and bacteria include; nucleus, cytoplasm, cell membrane, golgi apparatus, mitochondria, lysosomes, ribosomes, chromosomes, endoplasmic reticulum, vesicles, etc.

Golgi apparatus is also referred to as Golgi bodies and it functions as a packaging unit in living organisms, especially eukaryotic cells because it prepares protein and lipid molecules for export by chemically tagging them.

Hence, the Golgi apparatus (bodies) is an organelle involved in cell secretion through the transportation (export) of proteins and lipids out of a cell.

Given :

A 0.50-kg mass is attached to a spring of spring constant 20 N/m along a horizontal, frictionless surface.

The object oscillates in simple harmonic motion and has a speed of 1.5 m/s at the equilibrium position.

To Find :

At what location are the kinetic energy and the potential energy the same.

Solution :

Let, at location x from the equilibrium position the kinetic energy and the potential energy the same.

So,

[tex]P.E = K.E\\\\\dfrac{kx^2}{2} = \dfrac{mv^2}{2}\\\\x = v\sqrt{\dfrac{m}{k}}\\\\x = 1.5 \times \sqrt{\dfrac{0.5}{20}}\ m\\\\x = 0.238 \ m[/tex]

Hence, this is the required solution.

Answer:

D

Explanation:

Because the y axis is meter. If it is straight line at time and meter graph then it velocity and speed is 0

Answer:

RIGHT,  SAME SIZE,   VIRTUAL

Explanation:

Plane mirrors comply with the law of reflection where the angle of incidence is equal to the angle of reflection

therefore to complete the sentences:

A plane mirror produces images of objects that have an orientation that is RIGHT __, a size that is _SAME  SIZE____ (compared to that of the object) and a type that is VIRTUAL_____

Answer:

a)   p = 4.167 cm, b)   m = + 6

Explanation:

a) For this exercise we must use the equation of the constructor

          [tex]\frac{1}{f} = \frac{1}{p} + \frac{1}{q}[/tex]

where f is the focal length, p and q are the distance to the object and the image, respectively

In this case the distance to the image q = 25 cm and the focal length is f = 5.0 cm

Since the object and its image are on the same side of the lens, the distance to the image by the sign convention must be negative.

       [tex]\frac{1}{p } = \frac{1}{f} - \frac{1}{q}[/tex]

      [tex]\frac{1}{p} = \frac{1}{5} - \frac{1}{-25}[/tex]

      [tex]\frac{1}{ p}[/tex] = 024

      p = 4.167 cm

b) angular magnification

     m = h ’/ h = - q / p

     m = - (-25) /4.167

     m = + 6

the positive sign indicates that the image is straight and enlarged

Answer:

3 pls give me brainliest

Explanation:

Answer:

"8 units" is the appropriate answer.

Explanation:

According to the question,

Throughout equilibrium all particles are of equivalent intensity, and as such the integrated platform's total energy has been uniformly divided across all individuals.

Now,

The total energy will be:

= [tex]480+720[/tex]

= [tex]1200 \ units[/tex]

The total number of particles will be:

= [tex]50+100[/tex]

= [tex]150[/tex]

hence,

Energy of each A particle or each B particle will be:

= [tex]\frac{1200}{150}[/tex]

= [tex]8 \ units[/tex]

What is the primary evidence used to determine how the Moon formed?

[tex]\huge\color{purple}\boxed{\colorbox{black}{♡Answer}}[/tex]

A. Moon craters and Earth craters were caused by the same asteroid strike. ✅

[tex]\large\mathfrak{{\pmb{\underline{\orange{Happy\:learning }}{\orange{!}}}}}[/tex]

Answer: 28

Explanation:

Given

Circuit breaker current is [tex]I=20\ A[/tex]

Power of the light bulb is [tex]P=100\ W[/tex]

Voltage of the DC-circuit is [tex]V=120\ V[/tex]

If the resistance are connected in parallel, they must have same voltage i.e. 120 V

So, Resistance is given by

[tex]\Rightarrow R=\dfrac{V^2}{P}\\\\\Rightarrow R=\dfrac{120^2}{100}\\\\\Rightarrow R=144\ \Omega[/tex]

For the 20 A current and 120 V battery, net resistance is

[tex]\Rightarrow R_{net}=\dfrac{120}{20}\\\\\Rightarrow R_{net}=6\ \Omega[/tex]

Suppose there are n resistance in the circuit connected in parallel.

[tex]\Rightarrow \dfrac{144}{n}=R_{net}\\\\\Rightarrow n=\dfrac{144}{6}\\\\\Rightarrow n=28.8\approx 28\ \text{for current to be less than 20A}[/tex]

Thus, there can maximum of 28 bulbs.

Answer:

10J

Explanation:

KE = (1/2)mv²

100J = (.5)(40kg)v²

v²=(100J)/(20kg)

v²= 5

KE = 5(.5)(4kg)

KE = 10J

Answer:

T = 6.43 x 10⁻⁵ N.m

Explanation:

First, we will calculate the deceleration of the apparatus by using the third equation of motion:

[tex]2\alpha \theta = \omega_f^2-\omega_i^2[/tex]

where,

α = angular decelration = ?

θ = angular displacement = (236 rev)(2π rad/rev) = 1482.83 rad

ωi = initial angular speed = (24 rpm)(2π rad/1 rev)(1 min/ 60 s) = 2.51 rad/s

ωf = final angular speed = 0 rad/s

Therefore,

[tex]2\alpha(1482.83\ rad) = (0\ rad/s)^2-(2.51\ rad/s)^2\\\\\alpha = -\frac{(2.51\ rad/s)^2}{2965.66\ rad} \\\\\alpha = - 8.46\ x\ 10^{-4}\ rad/s^2[/tex]

negative sign shows deceleration

Now, for torque:

T = Iα

where,

T = Torque = ?

I = moment of inertia = 0.076 kg.m²

Therefore,

T = (0.076 kg.m²)(8.46 x 10⁻⁴ N.m)

T = 6.43 x 10⁻⁵ N.m

Answer:

 d = 178.57 10⁻⁹ m

Explanation:

For this exercise we must find the thickness to minimize the reflection, so the interference for the reflection must be destructive.

To find the expression we must take into account, two things:

* When the light goes from an index mordant medium to one with a higher refractive incoe, it undergoes a phase change of 180 (pi radians)

* within the film the wavelength of light is modulated by the index of refraction

           λₙ = λ₀/ n

In this case the light passes from the air to the reflective layer and undergoes a phase change of ∫π rad,  then it is reflected in the film-glass layer where it undergoes another phase change of π rad, therefore the total change of phase is 2π radians, this change is the or changes its value

period of the trigonometric functions, therefore its value does not change

  the expression for destructive interference is

           d sin θ = (me + ½) λₙ

           d sin θ = (m + ½) λ₀ / n

the minimum thickness occurs for m = 0 and if we take perpendicular incidence the sine = 1

          d = λ₀ /2 n

l

et's calculate

          d = 500 10⁻⁹ /( 2  1.4)

         d = 178.57 10⁻⁹ m

Answer:

η = 0.667 = 66.7%

Explanation:

The efficiency of the man can be given by the following formula:

η = output/input

where,

η = efficiency of man = ?

output = potential energy gain of the box = Wh

input = work done by man = Fd

Therefore,

[tex]\eta = \frac{Wh}{Fd}[/tex]

where,

W = weight of box = 200 N

h = height gained by box = 1 m

F = force exerted by man = 60 N

d = length of ramp = 5 m

Therefore,

[tex]\eta = \frac{(200\ N)(1\ m)}{(60\ N)(5\ m)}[/tex]

η = 0.667 = 66.7%

Given :

On the way home from school, Mr. X drives the first 10 miles at 55 mi/hr, the next 20 miles at 70 mi/hr, and the last 5 miles at 35 mi/hr.

To Find :

How far does Mr. X live from school.

Solution :

To find the distance between Mr. X residence from school is simply given by summing all the distance he travelled .

So, distance = 10 + 20 + 5 miles

distance = 35 miles.

Hence, this is the required solution.

u = 0.077

Explanation:

Work done by friction is

Wf = ∆KE + ∆PE

-umgx = ∆KE,. ∆PE =0 (level ice surface)

-umgx = KEf - KEi = -(1/2)mv^2

Solving for u,

u = v^2/2gx

= (12 m/s)^2/2(9.8 m/s^2)(95 m)

= 0.077

Kinetic friction is the ratio of the friction force to the normal force experienced by a body in moving state.The coefficient of kinetic friction between the ice and skates is 0.077.

Given-

velocity of the ice skater is 12 m/ sec.

Work done by the friction is the sum of the change of the kinetic energy and the change in potential energy.

[tex]W_{f}=\bigtriangleup KE +\bigtriangleup PE[/tex]

The value for the potential energy will be equal to Zero in this case. Therefore the work done by the friction is,

[tex]W_{f}=\bigtriangleup KE +0[/tex]

Kinetic energy is directly proportional to the mass of the object and to the square of its velocity and work done can be given as,

[tex]W_{f} =u_{f} mgx[/tex]

Here,  [tex]u_{f}[/tex] is friction force, [tex]m[/tex] is mass, [tex]g[/tex] is gravity and x is the distance .

Equate the value of kinetic energy and work done of friction for further result, we get,

[tex]u_{f} mgx=\dfrac{1}{2} \times mv^2[/tex]

[tex]u_{f} =\dfrac{1}{2gx} \times v^2[/tex]

[tex]u_{f} =\dfrac{1}{9.8\times 95} \times 12^2[/tex]

[tex]u_{f} =0.077[/tex]

Hence, the coefficient of kinetic friction between the ice and skates is 0.077.

For more about the friction, follow the link below-

https://brainly.com/question/13357196