If you had the opportunity to travel back in time and carry only one technological device that would help the world? What would? Why would you take it?​

Answer:

distance(d)=.....

time(t)=....

speed =?

we know that

speed =distance /time

The total distance covered by the subway train until is start from rest and again comes to rest is 435.36m.

The subway train starts from rest, and it accelerates to 1.6m/s² for 14s and after running for constant speed for about 70s and then it slows down at a rate of 3.5 m/s².

Now, while accelerating,

S = Ut + 1/2at²

U is initial speed, a is acceleration and t is time.

Putting values,

S = 1/2 x 1.6 x 14

S = 11.2m

Now,

V² - U² = 2aS

V is the constant speed,

V = √(2 x 1.6 x 11.2)

V = 5.98 m/s.

Distance covered with constant speed = 5.98 x 70

Distance S' covered with constant speed = 419.06 m.

Now, while the train slow down,

2a'S'' = V² - (0)²

a' = 3.5 m/s²

S'' = 5.10m

So, the total distance covered by the train will be (5.10 + 419.06 +11.2)m

The total distance covered by the train is 435.36 m.

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Answer:

Explanation:

We shall apply here Doppler's effect in optics . The formula is as follows

\(\frac{\triangle\lambda }{\lambda } = \frac{v}{c}\)

Δλ is change in wavelength , λ is original wavelength , v is velocity and c is velocity of light

Δλ = 685 - 590 = 95 nm

λ = 685

95 / 685 = v / 3 x 10⁸

v = .416 x 10⁸ m / s

= 4.16 x 10⁷ m /s

Answer:

Explanation:

0.120 rev/s(2π rad/rev) = 0.24π rad/s

At the highest point of the arc, gravity must supply the required centripetal acceleration. As the normal force is 1/4 of his normal weight, then 3/4 of gravity acceleration must be used as centripetal acceleration

0.75g = ω²R

R = 0.75(9.81) / (0.24π)²

R = 12.942198...

R = 12.9 m

The radius of the circle is equal to 12.95m which is rotating with an angular velocity of 0.120 rev/s.

A body spins in a vertical circle so that its motion at different points is different from the motion of the body is said to be vertical circular motion.

The velocity and tension vary in maximum magnitude from the lowest to the highest position because of the effect of the gravitational force of the earth.

Given, the angular velocity of the Ferris wheel, ω = 0.120 rev/s

ω = 0.120 rev/s × 2π rad/rev

ω= 0.7536 rad/s

If r is the radius of the circle and 'm' is the mass of the jack.

From newton's second law of motion, the net force will be equal to

mg - N = mrω²

mg - (mg/4) = mrω²

r = 3g/4ω²

r = 3×9.81 / (4× 0.7536)

r = 12.95 m

Therefore, the radius of the circle in which the jack travels is equal to 12.95m.

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Your question is incomplete, most probably the complete question was,

Jack sits in the chair of a Ferris wheel that is rotating at a constant 0.120 rev/s. As Jack passes through the highest point of his circular part, the upward force that the chair exerts on him is equal to one-fourth of his weight. What is the radius of the circle in which Jack travels?

The net force on the top block is 33.54 N.

Net force is the sum or resultant of two or more forces acting on a body.

Also, the net force is the force which is the sum of all the forces acting on an object simultaneously.

The sum of the upward forces is calculated as follows;

F(upward) = 50 N - 20 N = 30 N

The sum of the horizontal forces is calculated as follows;

F(horizontal) = 15 N

The net force or resultant force on the top block is calculated as follows;

F(net) = √Fy² + Fx²

where;

F(net) = √Fy² + Fx²

F(net) = √[(30)² + (15)²]

F(net) = 33.54 N

Thus, the net force or resultant force on the top block is determined as 33.54 N.

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Explanation:

A concave lens is also known as a diverging lens because it is shaped round inwards at the centre and bulges outwards through the edges, making the light diverge. They are used to treat myopia as they make faraway objects look smaller than they are.

Answer:

magnitude is 1382.59 N/C

Explanation:

Given the data in the question;

The time taken is;

t = x / v

we substitute;

t = ( 2 × 10⁻²) / ( 5.69  × 10⁶ )

t = 3.5149 × 10⁻⁹ s

next, the acceleration is;

a = 2y/t² = [2( 0.150 × 10⁻²)] / [ ( 3.5149 × 10⁻⁹ )² ]

a =  2.42826 × 10¹⁴ m/s²

now, the electric field is;

E = ma / q

we know that;

mass of electron m = 9.11 × 10⁻³¹ kg,

charge of electron q = 1.60 × 10⁻¹⁹ coulomb

we substitute

E = ( 9.11 × 10⁻³¹ )(2.42826 × 10¹⁴) / 1.60 × 10⁻¹⁹

E = 2.21214 × 10⁻¹⁶  / 1.60 × 10⁻¹⁹

E = 1.3826 × 10²¹

E = 1382.59 N/C

Therefore, magnitude is 1382.59 N/C  

The minimum mass required to be placed on the 0.00 cm mark of the meter stick to maintain equilibrium is 0.120 kg.

To maintain equilibrium, the torques acting on the meter stick must balance each other. The torque is given by the formula:

τ = r * F * sin(θ)

where τ is the torque, r is the distance from the pivot point to the point where the force is applied, F is the force applied, and θ is the angle between the force vector and the lever arm.

In this case, the meter stick is in equilibrium when the torques on both sides of the pivot point cancel each other out. The torque due to the weight of the meter stick itself is acting at the center of mass of the meter stick, which is at the 50.0 cm mark.

Let's denote the mass to be placed on the 0.00 cm mark as M. The torque due to the weight of M can be calculated as:

τ_M = r_M * F_M * sin(θ)

where r_M is the distance from the pivot point to the 0.00 cm mark (which is 30.0 cm), F_M is the weight of M, and θ is the angle between the weight vector and the lever arm.

Since the system is in equilibrium, the torques on both sides of the pivot point must be equal:

τ_M = τ_stick

r_M * F_M * sin(θ) = r_stick * F_stick * sin(θ)

Substituting the given values:

30.0 cm * F_M = 20.0 cm * (0.0400 kg * 9.8 m/s^2)

Solving for F_M:

F_M = (20.0 cm / 30.0 cm) * (0.0400 kg * 9.8 m/s^2)

F_M = 0.0264 kg * 9.8 m/s^2

F_M = 0.25872 N

Finally, we can convert the force into mass using the formula:

F = m * g

0.25872 N = M * 9.8 m/s^2

M = 0.0264 kg

Therefore, the minimum mass required to be placed on the 0.00 cm mark of the meter stick to maintain equilibrium is 0.120 kg.

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The magnitude of the vector is approximately 35.85 m.

The angle that this vector makes with the positive x-axis is approximately 32 degrees.

To find the magnitude of the vector with components Ax=29 m and Ay=18 m, we use the Pythagorean theorem:

|A| = √(Ax^2 + Ay^2)

|A| = √(29^2 + 18^2)

|A| = √(841 + 324)

|A| = √1165

|A| =  34.13 m

To find the angle that this vector makes with the positive x-axis, we can use the inverse tangent function:

θ = tan^-1(Ay/Ax)

θ = tan^-1(18/29)

θ = 31.82 degrees

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Answer:

An increase in angular speed due to conservation of energy priciple.

Explanation:

This leads to a decrease in your moment of inertia. This means that your angular velocity must increase as a result of conservation of energy principle and therefore you will spin faster.

It's also the same way this conservation of energy principle applies to ice skaters that makes them spin faster when they suddenly draw their arms inwards.

If a Catatlyst was added the values affected would be 2, 3, 4

A catalyst is a substance that speeds up the rate of a chemical reaction without undergoing any permanent change itself. It facilitates the reaction by providing an alternative pathway with lower activation energy, which allows the reaction to occur more readily.

Catalysts work by interacting with the reactant molecules and weakening the existing bonds or creating new ones, making it easier for the reaction to proceed.

Catalysts are typically specific to certain reactions and can be used in small amounts relative to the reactants. They play a crucial role in many industrial processes and are essential for efficient chemical transformations.

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Answer: Rectangular frames are easy to make but can get pulled out of shape. so if the sides are still attached , then the figure formed is parallelogram. useing the given measurement use the formula of a parallelogram.

formula : A = BASE X HEIGHT

Explanation:

Answer:

I was also going to ask same question edited:ok i found its true

This question involves the concepts of buoyant force and the weight of an object.

The buoyant force on the piece of metal is "8 N".

The apparent weight of the piece of metal is given by the following formula:

Apparent Weight = Actual Weight - Buoyant Force

Buoyant Force = Actual Weight - Apparent Weight

Buoyant Force = 20 N - 12 N

Buoyant Force = 8 N

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The attached picture illustrates the buoyant force.

The vector field that expresses the density of induced or permanent electric dipole moments in a dielectric medium is known as polarization density (also known as electric polarization or just polarization).

Thus, A dielectric is considered to be polarized when its molecules acquire an electric dipole moment when exposed to an external electric field.

Electric polarization of the dielectric is the term used to describe the electric dipole moment induced per unit volume of the dielectric material.

The forces that emerge from these interactions can be calculated using the polarization density, which also defines how a material reacts to an applied electric field and how it modifies the electric field. It is comparable to magnetization, which measures a material's equivalent response.

Thus, The vector field that expresses the density of induced or permanent electric dipole moments in a dielectric medium is known as polarization density (also known as electric polarization or just polarization).

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The neighbour weighs Iron. As he is a blacksmith, iron is the only thing he weighs the whole day.

A riddle is a statement, question or phrase having a double or veiled meaning, put forth as a puzzle to be solved.

If Robert, your neighbor, a forty-five-year-old blacksmith is seven feet tall, and eats all day long, based on these statements, we can explain the riddle as Robert weighs iron for the fact that he  is a blacksmith, iron is the only thing he weighs the whole day.

Thus, the correct explanation for the riddle is " The neighbour weighs Iron. As he is a blacksmith, iron is the only thing he weighs the whole day.

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No, the kinetic energy of the moving molecules in the sea water cannot be extracted for use. Details about kinetic energy can be found below.

Kinetic energy is a form of energy that is produced as a result of motion i.e. it is the energy possessed by a moving body.

This means that the kinetic energy of a moving body is specific to that body and dependent on the movement of that body. The kinetic energy is quickly converted to potential energy once the body stops moving.

Therefore, the kinetic energy of the moving molecules in the sea water cannot be extracted for use.

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So, if the object is on the Moon, its weight will be 63.2 N.

Hi ! This time I will help you to discuss the weight of objects. Weight is not mass, because weight is affected by the acceleration of gravity. As for the mass of an object, its value will never change, whether in one place, another place, another planet, or even in outer space. The relationship between weight, mass, and gravitational acceleration can be formulated in the equation:

\( \boxed{\sf{\bold{w = m \times g}}} \)

With the following condition :

We know that :

What was asked :

Step by step :

\( \sf{w = m \times g} \)

\( \sf{w = 39.5 \times 1.6} \)

\( \boxed{\sf{w = 63.2 \: N}} \)

So, if the object is on the Moon, its weight will be 63.2 N.

Answer:

oof ok

Explanation:

Thank you :)

Answer:

a. The object is moving with a constant velocity.

Answer:

support lights as a wave

Explanation:

In the model of light as a particle, the experimenter would expect to see one small hole of light emerging on the wall. However, as the light spreads out, it behaves much like a wave that diffracts when going through a small hole.

Answer:

The higher the energy, the shorter the wavelength.

Explanation:

Answer:

A

I say this because exponential growth takes place when a population per Capita growth stays the same

Answer:

B. 10.08

C.2448

Explanation:

Physics deal with objects small as subatomic particles and large as galaxies.

These numbers are difficult to write, so it is much more convenient to write them in scientific notation.

The potential energy of the roller coaster is 176,400 J (joules).

The potential energy of an object is given by the formula PE = mgh, where PE is the potential energy, m is the mass of the object, g is the acceleration due to gravity, and h is the height or vertical position of the object.

In this case, the roller coaster is at a peak of 20m and has a mass of 900kg. The acceleration due to gravity, g, is approximately 9.8 \(m/s^2\).

Using the formula, we can calculate the potential energy:

PE = mgh

= (900 kg)(9.8 \(m/s^2\))(20 m)

= 176,400 J

Therefore, the potential energy of the roller coaster is 176,400 J (joules).

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Hi! digital forensics is important because not only does digital forensics allow cyber security organisations to develop technologies that can prevent hackers from accessing devices, websites and networks but can lead businesses in the direction of understanding exactly what data is compromised.

Answer:

A student is conducting a pendulum experiment. Which of the following pieces of safety equipment would be the most vital to conduct this test?

Explanation:bkdbjkfej jf jfekjwniorigoexhndvgkj...............aplokdiuhyfgbv ..............................................

The earthquake would occur 13 minutes before 10:05 a.m. which will be at 9.52 am.

The p-waves travel with a constant velocity of 7 km/s

The time can be calculated by using the formula

t = d / v

where

T1 =  10:05 a.m

d is the distance they take to travel from the epicenter

v is the speed of the p-waves

On average, the speed of p-waves is

v = 7 km/s

d = 5600 km (given)

Substituting the values in the formula;

t = d / v

t = 5600 ÷ 7

t = 800 seconds

Converting into minutes,

t = 800 ÷ 60

t = 13.3

≈ 13 mins

T1 -  13 mins = T2

10:05 - 13 mins = 9.52 am

It means the earthquake occurred prior 13 minutes, that is at 9.52 am.

Therefore, the earthquake occurred at 9.52 am.

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