Tony walks at an average speed of 70 m/min from his home to
school. If the distance between his home and the school is
2100 m, how much time does it take for Tony to walk to
school?
min

Answer:

Option (b).

Explanation:

A star is a heavenly body which emits a tremendous amount of energy by the reaction of nuclear fusion.

Sun is the smallest star in the universe.

The star stars from the proto star, this is the process of birth of a star. Then it collapse due to the gravitational pull and then it tarts emit light and energy and become a star.

After the long long time, it starts to decay and become a neutron star or the black hole.

So, the correct option is (b).

The solution and answer are well written in the Pic above.

Answer:

the combination,decomposition or replacement that occurs in the molecules of matter during chemical change called chemical reaction

Answer:

A chemical change happens when one chemical substance is transformed into one or more different substances, such as when iron becomes rust. ... A chemical change is different from a physical change, which doesn't rearrange atoms or molecules and produce a completely new substance.

Explanation:

Obviously vector quantity

Answer:

Period refers to the time for something to happen and is measured in seconds/cycle

Answer:

What is the period of time? 5.62 Seconds

What is the amplitude? 1 Centimeters

Explanation:

it just makes sense

Answer:

the DISTANCE between the lever arm and the force is always 90º

Explanation:

In this exercise, you are asked to complete the missing words so that the phrase makes sense.

note that the torque is

              τ = F x r

where bold indicates vectors

When the rope is pulled, the DISTANCE between the lever arm and the force is always 90º

Answer:

Mass = 64,870,000,000 kilograms

Explanation:

Given the following data;

Density = 998 kg/m³

Volume = 6,500,000 m³

To find the mass of water in the reservoir;

Density can be defined as mass all over the volume of an object.

Simply stated, density is mass per unit volume of an object.

Mathematically, density is given by the equation;

Density = mass/volume

Making mass the subject of formula, we have;

Mass = density * volume

Mass = 998 * 6,500,000

Mass = 64,870,000,000 kilograms

Speed = distance /  time

Speed = 12km /  5 minutes

Speed = 2.4 km per minute

Speed is measured per hour, 1 hour has 60 minutes.

2.4 km per minute x 60 minutes = 144 km per hour

Answer:

A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place". Examples commonly are plants unwanted in human-controlled settings, such as farm fields, gardens, lawns, and parks

Answer:

Hence, the height of the ceiling at the center is 44.72 feet.

Explanation:

Consider that a whispering gallery has a length of 120 feet, and the foci are located 40 feet from the center.

Assume that the shape is a horizontal semi-ellipse with a center (0,0) and has the equation,

[tex]\frac{x^{2} }{ a^{2} } + \frac{y^{2} }{b^{2} } =1[/tex]  where a>b,

so,

2a = 120

a = 60

and

c = 40

Therefore, the equation of the ellipse is,

[tex]c^{2} = a^{2} -b^{2} \\\\40^{2} = 60^{2} -b^{2}\\\\b^{2} =2000\\\\b= 44.72.[/tex]

Answer:

2r or diameter

Explanation:

After 3 1/2 rounds it will end up on the other side of the circle and displacement will be 2 x the radius = d

Distance = 7 π R

Displacement = 2 R from the starting point directed through the center of the circle

[tex]speed = \frac{distance}{time} \\ = > \frac{200m}{min} = \frac{1500m}{t} \\ = > \frac{200m}{60s} = \frac{1500m}{t} \\ = > \frac{10m}{3s} = \frac{1500m}{t} \\ = > t = 1500m \times \frac{3s}{10m} \\ = > t = 150 \times 3s \\ = > t = 450s \: [/tex]

This is the answer.

Hope it helps!!

Answer:

Gravity

Explanation:

There's no gravity on space so you're floating

Explanation:

average speed is the total distance divided by total time

Answer:

cemento potque es plano

In component form, the displacement vectors become

• 350 m [S]   ==>   (0, -350) m

• 400 m [E 20° N]   ==>   (400 cos(20°), 400 sin(20°)) m

(which I interpret to mean 20° north of east]

• 550 m [N 10° W]   ==>   (550 cos(100°), 550 sin(100°)) m

Then the student's total displacement is the sum of these:

(0 + 400 cos(20°) + 550 cos(100°), -350 + 400 sin(20°) + 550 sin(100°)) m

≈ (280.371, 328.452) m

which leaves the student a distance of about 431.8 m from their starting point in a direction of around arctan(328.452/280.371) ≈ 50° from the horizontal, i.e. approximately 431.8 m [E 50° N].

Answer:

To find the height the following formula should be used:  

v 2 = u 2 + 2aH

Explanation:

Assuming this occurs on earth,  a= 9.8 ms -2

 -2        2

12=0+2 x9.8 x H

144

_______ =H

2 x 9.8

H= 7.35m

Answer:

-8.036 kV/m

Explanation:

The electric field E = -ΔV/Δx where ΔV = change in electric potential = V - V' where V = electric potential at x = 5.6 cm =  450 V and V' = electric potential at x = 0 cm, = 0 V . So, ΔV = V - V' = 450 V - 0 V = 450 V.

Δx = distance between the 0 V plate and the 450 V point = 5.6 cm = 0.056 m

So, E = -ΔV/Δx

Substituting the values of the variables into the equation, we have

E = -ΔV/Δx

E = -450 V/0.056 m

E = -8035.7 V/m

E = -8.0357 kV/m

E ≅ -8.036 kV/m

Since the electric field between two parallel conducting plates is constant, the electric field between the plates is E = -8.036 kV/m

Answer:

I believe in aliens but I do not think everyone should. I started to believe in aliens since the US government said they would be taking extraterrestrial life seriously. They will be in our lives sooner or later, so we shouldn't be ignoring their presence. I believe them because surveys show that nearly half of Americans believe that aliens have visited the Earth, either in the ancient past or recently. That percentage has been increasing. Belief in alien visitation is greater than belief that Bigfoot is a real creature, but less than belief that places can be haunted by spirits. Also there have been a lot of UFO sightings, and a Navy Jet has a video of that as well. These small things is just hard to ignore, and they make me and hopefully others believe in aliens.

Answer:

As a liquid is cooled its molecules lose kinetic energy and their motion slows. When they've slowed to where intermolecular attractive forces exceed the collisional forces from random motion, then a phase transition from liquid to solid state takes place and the material freezes.

Answer:

[tex]d=58m[/tex]

Explanation:

From the question we are told that:

Initial Speed [tex]U=12m/s[/tex]

Time [tex]T=5.6s[/tex]

Angle [tex]\theta=30[/tex]

Generally the  Newton's equation for motion is mathematically given by

[tex]d=d'+ut+\frac{at^2}{2}[/tex]

[tex]d=12cos30*5.6[/tex]

[tex]d=58m[/tex]

Answer:

heuristic.

Explanation:

Psychology can be defined as the scientific study of both the consciousness and unconsciousness of the human mind such as feelings, emotions and thoughts, so as to understand how it functions and affect human behaviors in contextual terms.

This ultimately implies that, psychology focuses on studying behaviors and the mind that controls it.

A heuristic is an automatic mental shortcut or rule of thumb that avail people the opportunity to make quick and efficient judgement in decision-making process, as well as proffering solutions to a problem. Thus, it allows people to make decisions, pass probability judgement or proffer solutions to problem quickly and efficiently while applying minimal mental effort.

Basically, a heuristic helps an individual to shorten the decision-making time while paying less attention on thinking of his or her next course of action.

Hence, when you're advised to try working backward from the desired goal to the starting point or current state. This advice describes a heuristic.

Answer:

(4) A = 3 A, A₂ = 11 A

(5) 7 A

Explanation:

(4)

From the diagram,

A = 3+6+2

A = 11 A

V = A₂R

A₂ = V/R₂............ Equation 1

Given: V = 12 V,  R₂ = 4 Ω

Substitute these values into equation 1

A₂ = 12/4

A₂ = 3 A

(5) Applying,

V = IR'

I = V/R'............ Equation 1

Where V = Voltage, I = cuurent, R' = total resistance.

But,

1/R' = (1/3)+(1/4)

1/R' = (3+4)/12

1/R' = 7/12

R' = 12/7 Ω

Given: V = 12 V

Substitute these values into equation 1

I = 12/(12/7)

I = 7 A

Therefore

A = 7 A

Answer:

Explanation:

1)Melting:

Melting is the process by which a substance changes from the solid phase to the liquid phase. ... Melting occurs when the internal energy of a solid increases, usually through the application of heat or pressure, such that the molecules become less ordered.

2) liquefication:

In physics and chemistry, the phase transitions from solid and gas to liquid (melting and condensation, respectively) may be referred to as liquefaction. The melting point (sometimes called liquefaction point) is the temperature and pressure at which a solid becomes a liquid.

3) vaporization:

Vaporization, conversion of a substance from the liquid or solid phase into the gaseous (vapour) phase. If conditions allow the formation of vapour bubbles within a liquid, the vaporization process is called boiling. Direct conversion from solid to vapour is called sublimation.

4) Sublimation occurs as molecules of a substance in the solid state go to the vapor state directly, rather than through the liquid state. ... ⭕In terms of the kinetic molecular theory, we know that molecules are in constant random motion, even when the substance is below the melting point.

oh this question seems to be difficult I don't think I can answer this

Answer:

01.

Explanation:

Half the acceleration. Its heavier and moves slower. If it moved the same acceleration, the forces would also have to be doubled since the mass was.

Answer:

519.62 m/s

Explanation:

Applying,

v = √(T/m').............. Equation 1

Where v = velocity of the wave, T = Tension on the string, m' = mass per unit length of the string

From the question,

Given: T = 1350 N, m' = 0.005 kg/m

Substitute these values into equation 1

v = √(1350/0.005)

v = √(270000)

v = 519.62 m/s

Answer:

a) pressure means force acted on a body per unit area

Magnitude of acceleration

Explanation:

We know that acceleration can increase depending in the force applied on an object, any object with a greater mass will apply a greater force. F = M(a).

This Newton's second law establishes a relationship between the summary of the external force and the acceleration of the body,  It is demonstrated with the change in the direction and magnitude of the acceleration in the experiment

Newton's second law establishes a relationship between the net force and the acceleration, according to the expression

          ∑ F = m a

where ∑F is the sum of the external forces, m the mass and the acceleration of the body

In this case we have an initial situation, the block and a baking mass, therefore an acceleration is created towards the hanging mass given by

           W₁ = M₁ g

            F = ma

          M₁ g = m a

          a = [tex]\frac{M_1}{m} \ g[/tex]

where W₁ and M₁ are the weight and the masses of the mass of the body hanging under the acceleration of gravity.

In the second case, perhaps you have two masses, one on each side,

         ∑ F = W₁ -W₂

          ∑F = (M₁ -M₂) g

let's use Newton's second law

          (M₁ -M₂ ) g = m a

           a = [tex]\frac{M_1 - M_2}{m} \ g[/tex]

We can see that in the second case the acceleration depends on the difference of the hanging masses. This is a proof of Newton's second law where the effect on acceleration is due to the sum of all external forces and not of each force individually.

In conclusion with the realization of this experiment  demostrate the valid true of Newton's second law

Learn more about Newton's second law here:  https://brainly.com/question/19860811

Answer:

The time of motion is 333.3 s

The angular acceleration is -0.0045 rad/s²

Explanation:

Given;

angular distance of the flywheel, θ = 40 rev

initial angular speed, [tex]\omega_i[/tex] = 1.5 rad/s

When the wheel comes to rest, the final angular speed, [tex]\omega_f[/tex] = 0

The angular acceleration is calculated as follows;

[tex]\omega_f^2 = \omega_i^2 + 2\alpha \theta \\\\0 = (1.5 \ rad/s)^2 + 2\alpha (40 \ rev\times \frac{2\pi \ rad}{1 \ rev} )\\\\0 = 2.25 + 160\pi \alpha\\\\160\pi \alpha = - 2.25\\\\\alpha = -\frac{2.25 }{160\pi} \\\\\alpha = -0.0045 \ rad/s^2[/tex]

The time of motion is calculated as;

[tex]\omega_f = \omega _i + \alpha t\\\\0 = 1.5 + (-0.0045t)\\\\0 = 1.5 - 0.0045t\\\\0.0045t = 1.5\\\\t = \frac{1.5}{0.0045} = 333.3 \ s[/tex]