state physical quantity represented by the gradient of a displacement - time graph

Answers

Answer 1

Answer:

velocity

Explanation:

this is because velocity has both magnitude and direction


Related Questions

Using your Periodic Table, which of the elements below is most likely to be a solid at room temperature?
A.) potassium, B.) Hydrogen, C.) Neon, D.) Chlorine

Answers

The answer is definitely Potassium

You're driving down the highway late one night at 20 m/s when a deer steps onto the road 35 m in front of you. You reaction time before stepping on the brakes is 0.50 s, and the maximum deceleration of your car is 10 \mathrm { m } / \mathrm { s } ^ { 2 }10m/s 2 . a. How much distance is between you and the deer when you come to a stop

Answers

Answer:

Explanation:

Discount the time here; it's not important. It doesn't tell you how long it takes the car to stop, it only refers to reaction time, which means nothing in the scheme of things.

The useful info is as follows:

initial velocity = 20 m/s

final velocity = 0 m/s

a = -10 m/s/s

and we are looking for the displacement. Use the following equation:

[tex]v^2=v_0^2+2a[/tex]Δx

where v is the final velocity, v₀ is the initial velocity, a is the deceleration (since it's negative), and Δx is displacement. Filling in:

[tex]0^2=(20)^2+2(-10)[/tex]Δx and

0 = 400 - 20Δx and

-400 = -20Δx so

Δ = 20 meters

An object is thrown from the ground with an initial velocity of 30 m/s. What is the velocity at the point 25 m above the ground?

Answers

Answer:

It's a pretty simple suvat linear projectile motion question, using the following equation and plugging in your values it's a pretty trivial calculation.

V^2=U^2+2*a*x

V=0 (as it is at max height)

U=30ms^-1 (initial speed)

a=-g /-9.8ms^-2 (as it is moving against gravity)

x is the variable you want to calculate (height)

0=30^2+2*(-9.8)*x

x=-30^2/2*-9.8

x=45.92m

Answer:

35

Explanation:

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If if two non zero vectors are acted on a body in what condition the resultant vector on the body will be zero ?

Answers

Answer:

Yes, when the 2 vectors are same in magnitude and direction. Yes, when the 2 vectors are same in magnitude but opposite in sense. Yes, when the 2 vectors are same in magnitude making an angle of 2π3 with each other.

Explanation:

Hope it helps you

The condition under which the resultant of two vectors will be zero is that the vectors must be in equilibrium.

The conditions under which the resultant of two non zero vectors acting on a body must be zero.

the two vectors must be in equilibriumthe two vectors are forces, then they must lie on the same plane and their line of action must pass through a common point.

[tex]\bar R = \bar R_A + \bar R_B = 0[/tex]

Thus, the condition under which the resultant of two vectors will be zero is that the vectors must be in equilibrium.

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25 POINTS 25 POINTS 25 POINTS 25 POINTS 25 POINTS

Assignment: Build an Electromagnet and a Motor Investigation

Electromagnet
1. How many paper clips did the wire wrapped around the nail just a few times pick up?

2. Which electromagnet design was most successful in picking up the most paper clips?

3. Would wrapping the wire more times around the nail make the electromagnet stronger or weaker?

4. What do you think the result would be if an iron nail that was much thicker was used?

5. What do you think would happen if a wooden stick was chosen as the core instead of the iron nail?

Motor
1. Describe the components that are necessary to make a motor run? What do they each provide? (example: battery provides voltage source)


2. Describe how the homemade motor makes mechanical energy from electrical energy.





3. What are three appliances in your house that use a motor that turns electrical energy into mechanical energy?

Answers

All the paper clips, coiled wire with nail and wrapping or coiling the wire more times are the correct answers.

All the paper clips will the wire wrapped around the nail just a few times pick up. A coiled wire with nail in the center is the electromagnet design which is most successful in picking up the most paper clips. Wrapping or coiling the wire more times around the nail make the electromagnet more stronger.

If an iron nail that was much thicker was used, it will make the magnet stronger that leads to strong electromagnetism. There are three main parts that is necessary for making a motor i.e. a rotor, a stator and a commutator.

These three parts use the attractive and repulsive forces of electromagnetism, causing the motor to spin continually as long as it receives a steady flow of electric current. Motors comprise of loops of wire in a magnetic field.

When current is passed through the loops, the magnetic field exerts a torque on the loops, which rotates the shaft that leads to the generation of electricity. Water pump, mixer and washing machine are three appliances in your house that use a motor that turns electrical energy into mechanical energy.

https://brainly.com/question/24278437

Vector A has magnitude of 8units and makes an angle of 45° with the positive x-axis. Vector B also has the same magnitude of 8units and directed along the negative x-axis. Find a. The magnitude and direction of A+B b. The magnitude and direction of A-B​

Answers

Answer:

Explanation:

Because vectors have direction and x and y components you can't just add them and say that their length is 16 because A is 8 units and so is B. What you're actually finding is the magnitude and direction of the vector that results from this addition. The magnitude is the length of the resultant vector, which comes from the x and y components of A and B, and the direction is the angle between the resultant vector and the positive x axis. To add the vectors, then, we need to find the x and y components of each. We'll do the x components of A and B first so we can add them to get the x component of C. Since x values are directly related to cos, the formula to find the x components of vectors is

[tex]V_x=Vcos\theta[/tex] which is the magnitude of the vector (its length) and the angle. Finding the x components of A:

[tex]A_x=8.0cos45[/tex] so

[tex]A_x=5.7[/tex] and for B:

[tex]B_x=8.0cos180[/tex] since the negative x axis is the 180 degree axis and

[tex]B_x=-8.0[/tex] If we add them, we get

[tex]C_x=-2.3[/tex]

Now onto the y components. The formula for that is almost the same as the x components except use sin instead of cos:

[tex]A_y=8.0sin45[/tex] so

[tex]A_y=5.7[/tex] and

[tex]B_y=8.0sin180[/tex] so

[tex]B_y=0[/tex] If we add them, we get

[tex]C_y=5.7[/tex]

Now for the final magnitude:

[tex]C_{mag}=\sqrt{(-2.3)^2+(5.7)^2}[/tex] and

[tex]C_{mag}=6.1 units[/tex] and now onto the direction.

The x component of C is positive and the y component is negative, which means that the direction has us at an angle is quadrant 2; we add 180 to whatever the angle is. Finding the angle:

[tex]tan^{-1}(\frac{C_y}{C_x})=(\frac{5.7}{-2.3})[/tex] = -68 + 180 = 112 degrees

The resultant vector of A + B has a magnitude of 6.1 and a direction of 112°

Do the same thing for subtraction, except if you're subtracting B from A, the direction that B is pointing has to go the opposite way. That means that A doesn't change anything at all, but B is now pointing towards 0.

[tex]A_x=5.7[/tex] (doesn't change from above)

[tex]B_x=8.0cos0[/tex] and

[tex]B_x=8.0[/tex] so

[tex]C_x=13.7[/tex] and

[tex]A_y=5.7[/tex] (also doesn't change from above)

[tex]B_y=8.0sin0[/tex] so

[tex]B_y=0[/tex] and

[tex]C_y=5.7[/tex] and for the magnitude:

[tex]C_{mag}=\sqrt{(13.7)^2+(5.7)^2[/tex] so

[tex]C_{mag}=15units[/tex] and for the direction:

[tex]tan^{-1}(\frac{5.7}{13.7})=23[/tex] and since both x and y components of C are in Q1, we add nothing.

And you're done!!!


Joule is equal to:
Awatt x metre
B.watt x second
C. Newton x Metre
D. Both b and c

Answers

Answer:

The answer is ( D) i. e both b and c.

A 117 kg horizontal platform is a uniform disk of radius 1.61 m and can rotate about the vertical axis through its center. A 62.5 kg person stands on the platform at a distance of 1.05 m from the center, and a 28.3 kg dog sits on the platform near the person 1.43 m from the center. Find the moment of inertia of this system, consisting of the platform and its population, with respect to the axis.

Answers

Answer:

I_syst = 278.41477 kg.m²

Explanation:

Mass of platform; m1 = 117 kg

Radius; r = 1.61 m

Moment of inertia here is;

I1 = m1•r²/2

I1 = 117 × 1.61²/2

I1 = 151.63785 kg.m²

Mass of person; m2 = 62.5 kg

Distance of person from centre; r = 1.05 m

Moment of inertia here is;

I2 = m2•r²

I2 = 62.5 × 1.05²

I2 = 68.90625 kg.m²

Mass of dog; m3 = 28.3 kg

Distance of Dog from centre; r = 1.43 m

I3 = 28.3 × 1.43²

I3 = 57.87067 kg.m²

Thus,moment of inertia of the system;

I_syst = I1 + I2 + I3

I_syst = 151.63785 + 68.90625 + 57.87067

I_syst = 278.41477 kg.m²

can anyone help me with this one​

Answers

Answer:

c) sin c /sin d

because light is moving from denser to shallower medium

b) refraction of light

Explanation:

Two manned satellites approach one another at a relative velocity of v=0.190 m/s, intending to dock. The first has a mass of m1=4.00×103 kg and the second a mass of m2=7.50×103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity?

Answers

Answer:

Their final relative velocity is 0.190 m/s

Explanation:

The relative velocity of the satellites, v = 0.190 m/s

The mass of the first satellite, m₁ = 4.00 × 10³ kg

The mass of the second satellite, m₂ = 7.50 × 10³ kg

Given that the satellites have elastic collision, we have;

[tex]v_2 = \dfrac{2 \cdot m_1}{m_1 + m_2} \cdot u_1 - \dfrac{m_1 - m_2}{m_1 + m_2} \cdot u_2[/tex]

[tex]v_2 = \dfrac{ m_1 - m_2}{m_1 + m_2} \cdot u_1 + \dfrac{2 \cdot m_2}{m_1 + m_2} \cdot u_2[/tex]

Given that the initial velocities are equal in magnitude, we have;

u₁ = u₂ = v/2

u₁ = u₂ = 0.190 m/s/2 = 0.095 m/s

v₁ and v₂ = The final velocities of the satellites

We get;

[tex]v_1 = \dfrac{2 \times 4.0 \times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 - \dfrac{4.0 \times 10^3- 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]

[tex]v_2 = \dfrac{ 4.0 \times 10^3 - 7.50\times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 + \dfrac{2 \times 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]

The final relative velocity of the satellite, [tex]v_f[/tex] = v₁ + v₂

∴ [tex]v_f[/tex] = 0.095 + 0.095 = 0.190

The final relative velocity of the satellite, [tex]v_f[/tex] = 0.190 m/s

Q010) A well in which the water rises on its own to a level above its aquifer Group of answer choices is the result of pressure within a confined aquifer that creates a potentiometric surface. is called an ordinary well. always pushes water higher than the ground surface. cannot be used for commercial or public use, as the water is under too much pressure.

Answers

Answer:

The result of pressure within a confined aquifer that creates a potentiometric surface

Explanation:

There are conditions under the Earth's surface, where porous rock layers are tilted and also have a confining, less porous, rock layer about the their boundary, forming a confined aquifer. The existing pressure in the aquifer is therefore confined within the water and the porous  rock layer, such that drilling into the pressurized aquifer leads to the water rising under the pressure existing in the aquifer, to a potentiometric surface which is above the actual underground level of the aquifer

Can I answer my own question

Answers

Answer:

Well okay do it what's your question ?

Answer:

yes

Explanation:

Why does the Earth exert a gravitational force on objects on its surface?
A. It has an atmosphere,
B. It has mass
C. It has a magnetic field.
D. It is so dense.

Answers

Answer:

B. It has mass

Explanation:

The Newtons Universal gravitacion law is : F = G.[tex]\frac{m1 m2}{d^{2} }[/tex]  , where F is the force exerted , m1 and m2 are the earth's mass and the object's mass, d is the distance and G the gravitacional constant. Comparing to the options we can say that the Earth exerts a gravitational force on objects on its surface because of its mass.

Please help! Will mark Brainliest

Answers

Explanation:

I think it is the third image as marked in the diagram I kept above because as we know first class levers have the fulcrum between the force and the load

En un rio una Onda viaja con una velocidad de propagación de 50 m/s con una longitud de Onda de 40 metros. Hallar la frecuencia de la Onda.

Answers

Answer:

Frequencia = 1.25 Hz

Explanation:

Dados los siguientes datos;

Velocidad = 50 m/s Longitud de onda = 40 metros

Para encontrar la frecuencia de la onda;

Matemáticamente, la velocidad de una onda viene dada por la fórmula;

[tex] Velocidad = Longitud \; de \; onda * Frequencia [/tex]

Haciendo de la frecuencia el tema de la fórmula, tenemos;

[tex] Frequencia = \frac {Velocidad}{Longitud \; de \; onda} [/tex]

Sustituyendo en la fórmula, tenemos;

[tex] Frequencia = \frac {50}{40} [/tex]

Frequencia = 1.25 Hz

If you could travel 900 meters in 55 seconds, what is your speed?
(Answer in details=brainliest)

Answers

Answer:

The rate of change of distance is called speed it can also be defined as distance travelled per unit time,from these definition you can tell that the formula will be

speed=distance/time

in this question the distance is 900meters and the time is 55seconds therefore the speed will be:

s=900meters/55seconds

=16.36m/s

I hope this helps

standard unit definition​

Answers

Answer:

Standard units are the units we usually use to measure the weight, length or capacity of objects.

Answer:

THE SYSTEM OF UNITS WHICH IS AGREED BY THE INTERNATIONAL CONVENTION OF SCIENTISTS HELD IN FRANCE IN 1960 IS CALLED SI SYSTEM.

difference Between Newton's first and third law​

Answers

Explanation:

In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction.6 days ago

Newton first law state that anything in motion or on rest will continue to do so until an external force is applied on it

Newton 3rd law stare that every action have equal and opposite reaction

The question is given in the picture below.... please help me and mention all the steps..​

Answers

Answer:

a)water is turning into ice it is changing it's state from liquid to solid

b)B to C  ice is melting and it  is changing  it's state from solid to liquid

C to D water is boiling and it is changing it's state from liquid to vapours(steam)

c) temperature

At A 0

At B 0

At C 100

At D 100

Explanation: The temperature will remain 0 degrees Celsius until all the ice becomes water and the temperature will remain 100 degrees Celsius until all the  water changes into steam.

state and prove Newton's second law of motion ​

Answers

Answer:

HOPE IT HELP YOU A LOT :)

I prove it also .

Answer:

Newtons Second law of motion states that"The rate of change of momentum is directly proportional to the force applied"

The velocity ratio of a pulley system is 4. What does it means

Answers

Answer:

Velocity ratio = distance travelled by effort / distance travelled by load. Which is equal to effort arm / load arm. When velocity ratio (VR) is 4, the effort arm is greater than load arm.

state one similarity and one difference of sound of frequency 750Hz and ultrasound ​

Answers

Explanation:

Ultrasound refers to sound waves having frequencies greater than the frequency range limit. Ultrasound has the same physical qualities as "regular" (audible) music, except that individuals cannot hear it. Ultrasound devices use frequencies ranging from 20 kHz to a few gigahertz.

The frequencies of ultrasound utilised in clinical settings are generally between 2 and 12 MHz. Shorter wavelengths have a larger penetration depth into the body but less resolution; longer wavelengths have a greater depth of penetration but have a restricted depth of penetration.

Which of the following is true of highly conductive elements?

Answers

Answer:

A

Explanation:

i think a is the answer because if you take an example of group 1 and 2 metals on the periodic table you will notice that they are highly reactive but they have a few electrons in their outer most shells.

I hope this helps

What is concave mirror?​

Answers

Answer:

A concave mirror, or converging mirror, has a reflecting surface that is recessed inward (away from the incident light). Concave mirrors reflect light inward to one focal point. They are used to focus light.

A comet of mass 2 × 10^8 kg is pulled toward the star. If the comet's initial velocity is very small, and the comet starts moving toward the star from 700,000,000 km away, how fast is it going right before it hits the surface of the star? (Assume that it does not lose any mass by melting as it approaches the star.)

Answers

Answer:

The speed of the comet at the surface of the star is approximately 1,208,694.7 m/s

Explanation:

Question parameter obtained online; The mass of the star, M = 5 × 10³¹ kg

Explanation;

The given mass of the comet, m = 2 × 10⁸ kg

The initial velocity of the comet, v → 0

The distance of the comet from the star, d = 700,000,000 km

The gravitational potential at d = G·M·m/d

The kinetic energy of the comet, K.E. = m·v²/2

The kinetic energy of the comet at d = m·(0)²/2 = 0

The gravitational potential at the surface of the star, R = G·M·m/R

The kinetic energy of the comet at the surface of the star, R = m·(v)²/2 = 0

Where;

M = The mass of the star = 5 × 10³¹ kg

[tex]M_{Sun}[/tex] = The mass of the Sun = 1.989 × 10³⁰ kg

M/[tex]M_{Sun}[/tex] = 5 × 10³¹/(1.989 × 10³⁰) ≈ 25

G = The universal gravitational constant = 6.67430 × 10⁻¹¹ N·m²/kg²

R = The radius of the star

Therefore, we have;

m·(0)²/2 - G·M·m/d = m·v²/2 - G·M·m/R

∴ v = √((G·M·m/R - G·M·m/d)×2/m) = √(2·G·M(1/R - 1/d))

Therefore; v = (2 × 6.67430 × 10⁻¹¹ × 5 × 10³¹ × (1/R - 1/700,000,000,000))

v = 81696389149.1×√(1/R - 1/700,000,000,000).

The speed of the comet at the surface of the star, v = 81696389149.1×√(1/R - 1/700,000,000,000)

The mass radius relationship is given as follows;

[tex]\dfrac{R}{R_{Sun}} = 1.30 \times \left(\dfrac{M}{M_{Sun}} \right)^{\dfrac{1}{2} }[/tex]

[tex]R = R_{Sun} \times 1.30 \times \left(\dfrac{M}{M_{Sun}} \right)^{\dfrac{1}{2} }[/tex]

The radius of the Sun = 696,340,000 M

∴ R ≈ 696,340,000 × 1.3 × √(25.14) = 4538865694.76

R = 4538865694.76 m

v = 81696389149.1×√(1/4538865694.76 - 1/700,000,000,000) ≈ 1208694.7  m/s

Which of the following is occurring while a satellite is in orbit around Earth? O It is continuously pulling away from Earth It is continuously falling toward the surface of Earth. It stays in a constant speed orbit where it was oriented from the start. It stays in the same orbit orientation traveling at variable speeds.​

Answers

AnswerIt is continuously falling towards the surface of the earth

Explanation:

since gravity from earth is the thing that keeps it constantly in orbit

J.J. Thomson theorized that, if an atom had all of its negatively charged
electrons removed, the remaining material would be
A. neutral
B. negatively charged
C. positively charged
D. magnetic

Answers

Answer:

C. Positively charged

Explanation:

The plum pudding model of the atom proposes by J. J. Thomson consisted of electrons which lay embedded as the raisins within a dough or soup that was positively charged. The electron was discovered by J. J. Thomson in 1897 through cathode ray tube experiments.

Based on the plum pudding model, if all the negatively charge electrons contained in an atom are removed, the material remaining will be the positively charged soup

Pls help me solve these two questions!!! Tq​

Answers

Answer:

Part A would be 80 Joules and Part B would be 20 meters.

Explanation:

For Part A:

The first step is to convert the mass to SI units.

400 g = 0.4 kg

Next, we need to know that the law of conservation of energy states that the total energy of an isolated system is conserved. In this case, it means that the total energy at the bottom, where kinetic energy is greatest, will be equal to the total energy at the top, where gravitational potential energy is greatest.

Max Gravitational Potential Energy = Max Kinetic Energy

Max Gravitational Potential Energy = [tex]\frac{1}{2} mv^{2}[/tex]

Max Gravitational Potential Energy = [tex](\frac{1}{2} )(.4kg)(20m/s)^2[/tex] = 80[tex]J[/tex]

For Part B:

We need to once again set gravitational potential energy to kinetic energy, only this time we use the GPE equation and solve for height. We already solved for the kinetic energy so we just plug everything in and solve.

[tex]mgh = \frac{1}{2} mv^{2}[/tex]

[tex](.4kg)(10m/s^{2} )h = 80J\\h = 20m[/tex]

why does the satellite not fall while revolving the earth​

Answers

Answer:

Satellites don't fall from the sky because they are orbiting Earth. Even when satellites are thousands of miles away, Earth's gravity still tugs on them. Gravity--combined with the satellite's momentum from its launch into space--cause the satellite go into orbit above Earth, instead of falling back down to the ground.

Q: Riri wants to bake a cake. She adds flour, sugar, egg, baking soda, and yeast into a bowl and mixed them together. After all the ingredients are mixed, she leaves the dough for 30 minutes and the dough starts to rise. Which changes Occurred in this process? Explain your reason.​

Answers

Answer:

I don't know what you mean about which changes occurred in this process but if its why the dough starts rising then its caused by the carbon dioxide in baking soda and yeast which is a fungus

Answer:

When baking,flour is mixed with water,the other ingredients and yeast to form a paste called a dough.what happens is that the zymase enzyme from the yeast acts on the sugars to form carbon dioxide and alcohol.the carbon dioxide begins to form bubbles in the dough causing it to rise..

I hope this helps

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