What kind of model is shown below?
O A. A mathematical model
B. An experimental model
O C. A computer model
D. A physical Model

Answer:

f = 1.255 cm

Explanation:

The Radius of Curvature:

The radius of that hollow sphere, whose part is the spherical mirror, is known as ‘The Radius of Curvature’ of  mirror.

Focal Length:

The distance between principal focus and pole is called ‘Focal Length’. It is denoted by ‘F’

The focal length is basically equal to the half of the radius of curvature of the mirror:

[tex]f = \frac{r}{2}[/tex]

where,

f = focal length = ?

r = radius of curvature = 2.51 cm

[tex]f = \frac{2.51\ cm}{2}[/tex]

f = 1.255 cm

Answer: 4 s

Explanation:

Given

The ball leaves the hand of student with a speed of [tex]u=19\ m/s[/tex]

When the hand is [tex]h=2.5\ m[/tex] above the ground

Using the equation of motion we can write

[tex]h=ut+\dfrac{1}{2}at^2[/tex]

Substitute the values

[tex]\Rightarrow 2.5=-19t+0.5\times 9.8t^2\\\Rightarrow 4.9t^2-19t-2.5=0\\\\\Rightarrow t=\dfrac{19\pm \sqrt{(-19)^2-4\times 4.9\times (-2.5)}}{2\times 19}\\\Rightarrow t=4.0049\quad [\text{Neglecting the negative value of }t][/tex]

Thus, the ball will take 4 s to hit the ground.

Answer: The mutual inductance of these solenoids is [tex]2.88 \times 10^{-7} H[/tex].

Explanation:

Given: Length = 50.0 cm (1 cm = 0.01 m) = 0.50 m

[tex]N_{1}[/tex] = 6750

[tex]N_{2}[/tex] = 15

Radius = [tex]\frac{0.120 cm}{2} = 0.6 cm = 6 \times 10^{-4} m[/tex]

As inner of a solenoid resembles the shape of a circle. So, its area is calculated as follows.

[tex]Area = \pi \times r^{2} = \pi \times (6 \times 10^{-4})^{2}[/tex]

Formula used to calculate mutual conductance of two solenoids is as follows.

[tex]M = \frac{\mu_{o} \times A \times N_{1} \times N_{2}}{l}[/tex]

where,

M = mutual conductance

A = area

[tex]\mu_{o}[/tex] = relative permeability = [tex]4 \pi \times 10^{-7} Tm/A[/tex]

[tex]N_{1}[/tex] = no. of coils in outer solenoid

[tex]N_{2}[/tex] = no. of coils in inner solenoid

l = length

Substitute the values into above formula as follows.

[tex]M = \frac{\mu_{o} \times A \times N_{1} \times N_{2}}{l}\\= \frac{4 \pi \times 10^{-7} Tm/A \times \pi (6 \times 10^{-4})^{2} \times 6750 \times 15}{0.5 m}\\= 2.88 \times 10^{-7} H[/tex]

Thus, we can conclude that the mutual inductance of these solenoids is [tex]2.88 \times 10^{-7} H[/tex].

Answer:

The speed of the proton is [tex]v =5.95\times 10^{5} m/s[/tex]

Explanation:

Energy, E = 1.85 keV

mass of proton, m = 1.67 x 10^-27 kg

Let the speed is v.

The kinetic energy is given by

[tex]K = 0.5m\times v^{2}\\\\1.85\times \1.6\times 10^{-16} = 0.5\times 1.67\times 10^{-27}\times v^{2}\\\\v =5.95\times 10^{5} m/s[/tex]

Answer:

(a) The magnitude of the change in internal energy is 6.623 x 10⁵ J

(b) the efficiency of the athlete is 10.94 %

Explanation:

Given;

work done by the athlete (system), W = 6.53 x 10⁴ J

the heat given off by the athlete (system), Q = 5.97 x 10⁵ J

The simple diagram below will be used to illustrate the direction of the energy flow assuming a heat engine.

                            Q← ⊕ →W

The work, W, points away from the system since the system does the work

The heat, Q, points away from the system since heat is given off

Apply first law of thermodynamic;

ΔU = Q + W

where;

q is the heat flowing into or out of the system

(+q     if the heat is flowing into the system

(-q      if the heat is leaving the system

w is the work done by or on the system

(+w     if the work is done on the system by the surrounding

(-w     if the work is done by the system to the surrounding

Thus, from the above explanation, the change in internal energy of the system is calculated as;

ΔU = -Q - W

ΔU = - 5.97 x 10⁵ J  -  6.53 x 10⁴ J

ΔU = -6.623 x 10⁵ J

The magnitude of the change in internal energy = 6.623 x 10⁵ J

(b) the efficiency of the athlete;

[tex]Efficiency = \frac{W}{Q} \times 100\%\\\\Efficiency = \frac{6.53 \times 10^4}{5.97 \times 10^5} \times 100\%\\\\Efficiency = 10.94 \ \%[/tex]

Answer:

The correct answer is - A matter that has an ordered arrangement of atoms, molecules, or ions.

Explanation:

In physics, a crystal is a type of solid matter in which a highly arranged molecule or atoms present to form a lattice that extended in all directions. It is a lightweight clear solid which is normally is colorless.

It can be cubic, hexagonal, triclinic, monoclinic, orthorhombic, tetragonal, and trigonal that are ordered arrangments. Its internal symmetry is visible to its surface.

Answer:

-4, -3, -2, -1, 0, 1, 2, 3, 4  

Explanation:

There are four sets of quantum numbers;

1) principal quantum number (n)

2)orbital quantum number (l)

3) magnetic quantum number (ml)

4) Spin quantum number (s)

These quantum numbers describes the probability of finding the electron within the atom.

The values of the magnetic quantum number depends on the orbital quantum number. The range of values of the magnetic quantum number is -l to +l

Hence, if the orbital quantum number of the hydrogen atom is 4, the permitted orbital magnetic quantum numbers will be; -4, -3, -2, -1, 0, 1, 2, 3, 4.  

Answer:   A 7.8 ·10^22 J  B   1.6 times  C 3.9 ·10^15 $

Explanation: A : Speed of light c =  3.0·10^8 m/s,  0.12·c = 3.6·10^7 m/s  

Mass is 120·10^6 kg . Change of kinetic energy

E = ½mv² =  0.5 · 120·10^6 kg · (3.6·10^7 m/s)² = 7.776·10^22 J

B  exponent is same , 7.776 / 5 = 1,55 times of energy use of Earth in year.

C  Energy is  7.776·10^22 J / 10^6  = 7.776·10^16 MJ

Price is 0.05 $ · 7.776·10^16 MJ = 3.888·10^15 $

A. The energy required to get to the cruising speed is 7.8×10²² J

B. The energy needed will be 1.56 times the total world energy

C. The cost price required to generate the energy needed by the spaceship is $ 3.9×10⁵

A. Determination of the energy

Mass (m) = 120×10⁶ Kg

Velocity of light = 3×10⁸ m/s

Velocity of spaceship = 0.12 × 3×10⁸ = 3.6×10⁷ m/s

E = ½mv²

E = ½ × 120×10⁶ × (3.6×10⁷)²

Thus, the energy needed is 7.8×10²² J

B. Comparing the energy needed to the total world energy.

Energy needed = 7.8×10²² J

World energy = 5×10²² J

Energy needed / World energy = 7.8×10²² / 5×10²²

Energy needed / World energy = 1.56

Cross multiply

Thus, the energy needed is 1.56 times the World energy

C. Determination of the cost required to generate the energy

1×10⁶ J = $ 0.05

Therefore,

7.8×10²² J = (7.8×10²² × 0.05) / 1×10⁶

7.8×10²² J = $ 3.9×10⁵

Therefore, the cost required to generate the energy is $ 3.9×10⁵

Learn more: https://brainly.com/question/10703928

Answer:

a. True

Explanation:

Pollution can be defined as the physical degradation or contamination of the environment through an emission of harmful, poisonous and toxic chemical substances.

Aside from toxic pollution, the other types of pollution includes the following;

I. Sediment pollution.

II. Nutrient pollution.

III. Bacterial pollution.

Furthermore, particulate pollution is a form of pollution that is responsible for the degradation of the environment.

Particulate matter is also referred to as particle pollution or atmospheric aerosol particles and it can be defined as a complex microscopic mixture of liquid droplets and solid particles that are suspended in air. Other forms of particle pollution includes space debris and marine debris.

Some examples of particulate pollution are dusts, soot, dirt, smoke, etc.

Answer:a

Explanation:

Answer:40 hour

Explanation:

Answer:

the value of the final pressure is 0.168 atm

Explanation:

Given the data in the question;

Let p₁ be initial pressure, v₁ be initial volume.

After expansion, p₂ is final pressure and v₂ is final volume.

So using the following equations;

p₁v₁ = nRT

p₂v₂ = nRT

hence, p₁v₁ = p₂v₂

we find p₂

p₂ = p₁v₁ / v₂

given that; initial volume v₁ = 0.175 m³, Initial pressure p₁ = 0.350 atm,

final volume v₂ = 0.365 m³

we substitute

p₂ = ( 0.350 atm × 0.175 m³ ) / 0.365 m³

p₂ = 0.06125 atm-m³ / 0.365 m³

p₂ = 0.168 atm

Therefore, the value of the final pressure is 0.168 atm

Answer:

kinetic energy of the train = 2,910.6 x 10⁷ joule

Explanation:

Given:

Mass of train = 3.3 x 10⁷ kg

Speed of train = 42 m/s

Find:

kinetic energy of the train

Computation:

kinetic energy = (1/2)(m)(v²)

kinetic energy of the train = (1/2)(3.3 x 10⁷)(42²)

kinetic energy of the train = (1/2)(3.3 x 10⁷)(1,764)

kinetic energy of the train = (3.3 x 10⁷)(882)

kinetic energy of the train = 2,910.6 x 10⁷ joule

Answer: The initial kinetic energy of the train is [tex]2910.6 \times 10^{7} J[/tex].

Explanation:

Given: Mass = [tex]3.3 \times 10^{7} kg[/tex]

Speed = 42 m/s

Kinetic energy is the energy acquired by an object due to its motion.

Formula to calculate kinetic energy is as follows.

[tex]K.E = \frac{1}{2}mv^{2}[/tex]

where,

m = mass of object

v = speed of object

Substitute the values into above formula as follows.

[tex]K.E = \frac{1}{2}mv^{2}\\= \frac{1}{2} \times 3.3 \times 10^{7} kg \times (42 m/s)^{2}\\= 2910.6 \times 10^{7} kg m^{2}/s^{2} (1 J = 1 kg m^{2}/s^{2})\\= 2910.6 \times 10^{7} J[/tex]

Thus, we can conclude that the initial kinetic energy of the train is [tex]2910.6 \times 10^{7} J[/tex].

Answer:

[tex]force = mass \times acceleration \\ 1200 = 400 \times a \\ a = \frac{1200}{400} \\ a = 3 \: {ms}^{ - 2} [/tex]

Answer: D) the temperature is not high enough.

Explanation:

The nuclear fusion reactions involve the fusion of the nucleus of the heavy metals. This is done in a nuclear reactor and energy is produced in the heat energy along with radiations. This system requires heat energy for the accomplishment of the nuclear reactions. The temperature of the system cannot be maintained inside the ocean so nuclear fusion will not occur in the ocean.

q=CV

q=(ϵ0×A)/(d)×(V)

(2.24×10^−9)=((8.08×10^−4)(8.85×10−12))/(d)× (855)

d=2.7294×10^-3

Answer: B. Raising the temperature results in the radiator giving off photons of high-energy ultraviolet light

Explanation:

Quantum theory explains the nature of matter and its behavior on the atomic level. It should be noted that at higher temperature, radiation is emitted by the blackbody at higher intensity and frequency.

Raising the temperature results in the radiator giving off photons of high-energy ultraviolet light. It should also be noted that there isn't a limit to the temperature of the blackbody.

The correct option is B.

Answer:

Explanation:

The CORRECT answer is C. Raising the temperature of the radiator causes more photons of a few possible energies to be emitted.

Quantum theory suggests that photons can only exist in a few possible energy states.

Energy coming off a radiator is usually in the infra-red light; not ultraviolet. So B is not the right answer.

Answer:

The total time it will take her to complete the race is 13.17 s

Explanation:

Given;

mass of the sprinter, m = 61.5 kg

acceleration of the sprinter, a = 3.7 m/s²

first distance covered, d₁ = 12 m

Determine her velocity for the first 12 m;

v² = u²  + 2as

v² = 0  +  (2 x 3.7 x 12)

v² = 88.8

v = √88.8

v = 9.42 m/s

Determine her time for the first 12 m;

v = u + at

9.42 = 0 + 3.7t₁

9.42 = 3.7t₁

t₁ = 9.42 / 3.7

t₁ = 2.55 s

Determine the time it will take her to complete the last 100 m at a constant velocity of 9.42 m/s

s = vt₂ + ¹/₂at₂²

s = vt₂ + ¹/₂(0)t₂²

s = vt₂

100 = 9.42t₂

t₂ = 100 / 9.42

t₂ = 10.62 s

The total time it will take her to complete the race = 2.55 s + 10.62 s

                                                                                    = 13.17 s

Answer:

The answer for this question is 50k N.m

Answer:

the speed in -y

Explanation:

For this exercise we must use the right hand rule. The motion of a positive charge is given by.

Thumb points in the direction of speed

fingers extended in the direction of the magnetic field, + z axis

the palm in the direction of the force, as the charge is negative in the opposite direction of the force, axis + x

therefore the thumb is in the direction - y

the speed in -y

Answer:

A) F = V²E_o•πr²/2d²

B) U = E_o•Aπr²V²/2d

Explanation:

A) Since we have two circular plates, the formula for the electric field is expressed as;

E = V/d

Where;

V is voltage

d is distance

However, the net electric field produced is given by;

E' = V/2d

The tension in the cable can then be expressed as;

F = qE'

Where q is charge

Thus;

F = qV/2d - - - (eq 1)

We also know that;

C = q/V = E_o•A/d

A is area = πr²

Thus;

q/V = E_o•πr²/d

q = VE_o•πr²/d

Let's put VE_o•πr²/d for q in eq 1 to get;

F = V²E_o•πr²/2d²

B) formula for the energy stored in the electric field is;

U = ½CV²

From earlier, we saw that; C = E_o•A/d

Thus;

U = ½E_o•AV²/d

A = πr²

Thus;

U = E_o•Aπr²V²/2d

Answer:

0.5 A

Explanation:

Applying,

V = IR.................. Equation 1

Where V = Voltage, I = current, R = Resistance.

make I the subject of the equation

I = V/R............... Equation 2

From the question,

Given: V = 75 V, R = 150 Ω

Substitute these values into equation 2

I = 75/150

I = 0.5 A.

Hence the cuurent through the resistor is 0.5 A

Answer:

The new force becomes (1/9)th of the original force.

Explanation:

The gravitational force between two masses is given by :

[tex]F=G\dfrac{m_1m_2}{r^2}[/tex]

Where

r is the distance between masses,

If the new distance is, r' = 3r

The new force is given by :

[tex]F'=G\dfrac{m_1m_2}{r'^2}\\\\F'=G\dfrac{m_1m_2}{(3r)^2}\\\\F'=\dfrac{1}{9}\times G\dfrac{m_1m_2}{r^2}\\\\F'=\dfrac{F}{9}[/tex]

So, the new force becomes (1/9)th of the original force.

Answer:

Physical adaptation

Explanation:

This is because the powerful legs of jackrabbit is an example of physical or structural adaptations because they are the physical features or characteristics that help jackrabit to survive or adapt in its natural environment. It makes it to run away from predators that might want to affect them. The structural adaptions help the animal to move ,eats and so on.

Answer:

The elevator must be moving upward.

Explanation:

During the motion of an elevator, the weight of the person deviates from his or her actual weight. This temporary weight during the motion is referred to as "Apparent Weight". So, when the elevator is moving downward, the apparent weight of the person becomes less than his or her actual weight.

On the other hand, for the upward motion of the elevator, the apparent weight of the person becomes more than the actual weight of that person.

Since the apparent weight (645 N) of the student, in this case, is greater than the actual weight (615 N) of the student.

Therefore, the elevator must be moving upward.

Answer: [tex]56.4\ m/s^2, 201.42\ m/s^2[/tex]

Explanation:

Given

Rocket attain a velocity of [tex]v=282\ m/s[/tex] in a time period of [tex]t=5\ s[/tex]

It was brought jarringly back to rest in only [tex]t'=1.4\ s[/tex]

Acceleration is the change in velocity of the object over a period of time

(a) Acceleration in his direction of motion

[tex]\Rightarrow a=\dfrac{v-0}{t}\\\\\Rightarrow a=\dfrac{282}{5}\\\\\Rightarrow a=56.4\ m/s^2[/tex]

(b) acceleration opposite to his direction of motion i.e. deceleration is

[tex]\Rightarrow a_d=\dfrac{0-v}{t'}\\\\\Rightarrow a_d=\dfrac{-282}{1.4}\\\\\Rightarrow a_d=-201.42 \ m/s^2\\\Rightarrow a_d=201.42\ \text{decelration}[/tex]

Answer:

1.00 × 10⁴ pieces of pizza

Explanation:

Step 1: Calculate the energy needed to watch the Super Bowl.

We need to produce energy to make an HDTV work (175 W) for 4 hours. First, we will convert, 4 hours to seconds using the conversion factor 1 h = 3600 s.

4 h × 3600 s/1 h = 14400 s

The energy required is:

14400 s × 175 J/s = 2.52 × 10⁶ J

We can convert this to calories using the conversion factor 1 cal = 4.184 J.

2.52 × 10⁶ J × 1 cal/4.184 J = 6.02 × 10⁵ cal

Step 2: Calculate the calories that the person should consume

Assuming an efficiency of 20% for the human body, the calories that a person should consume are:

6.02 × 10⁵ cal × 100/20 = 3.01 × 10⁶ cal

Step 3: Calculate the number of pieces of pizza to be consumed

Each piece of pizza contains 300 cal.

3.01 × 10⁶ cal × 1 piece/300 cal = 1.00 × 10⁴ pieces

Answer:

B) Inertia is the resistance of any physical object