At the base of a hill, a 90 kg cart drives at 13 m/s toward it then lifts off the accelerator pedal). If the cart just barely makes it to the top of this hill and stops, how high must the hill be?

Answer:

v = 2.57 m / s

Explanation:

For this exercise let's use conservation of energy

starting point. When it is at an angle of 30º

          Em₀ = K + U = ½ m v₁² + m g y₁

final point. Lowest position

          Em_f = K = ½ m v²

as there is no friction, the energy is conserved

          Em₀ = Em_f

          ½ m v₁² + m g y₁ = ½ m v²

Let's find the height(y₁), which is the length of the thread minus the projection (L ') of the 30º angle

         cos 30 = L ’/ L

         L ’= L cos 30

         y₁ = L -L '

          y₁ = L- L cos 30

we substitute

          ½ m v₁² + m g L (1- cos 30) = ½ m v²

           v = [tex]\sqrt{ v_1^2 +2gL(1-cos30 )}[/tex]

let's calculate

           v = [tex]\sqrt{ 2^2 + 2 \ 9.8 \ 1.0 (1- cos 30)}[/tex]

           v = 2.57 m / s

Answer:

50Kgm/s

Explanation:

Momentum=Mass*Velocity

P=mv

Given Mass=5Kg. Given Velocity=10m/s

Momentum=5*10=50Kgm/s

Answer:

102.5N

Explanation:

Given that  a delivery truck travels along a level stretch of road with constant speed, most of the power developed by the engine is used to compensate for the energy transformations due to friction forces exerted on the delivery truck by the air and the road. If the power developed by the engine is 4.12 hp, calculate the total friction force acting on the delivery truck (in N) when it is moving at a speed of 30 m/s. One horsepower equals 746 W

The power = 4.12 × 746 = 3073.52 W

Using the formula

Power = force × velocity

3073.52 = force × 30

Force = 3073.52 / 30

Force = 102.5 N

Since most of the power developed by the engine is used to compensate for the energy transformations due to friction forces exerted on the delivery truck by the air and the road, therefore,

the total friction force acting on the delivery truck (in N) when it is moving at a speed of 30 m/s is 102.5 N

Answer:

electric force

Explanation:

its a contact and noncontact force

Answer:

Δx = distance between central bright fringe and first bright fringe = 19.85 x 10⁻⁴ m = 1.985 mm

distance between central bright fringe and second dark fringe = 2.978 mm

Explanation:

We have the following data:

λ = wavelength of light = 641 nm = 6.41 x 10⁷ m

L = Distance of Screen from slits = 3.19 m

d = slit separation = 1.03 mm = 1.03 x 10⁻³ m

Δx = distance between consecutive bright fringes = fringe spacing = ?

Using formula:

[tex]\Delta x = \frac{\lambda L}{d}\\\\\Delta x = \frac{(6.41\ x\ 10^{-7}\ m)(3.19\ m)}{1.03\ x\ 10^{-3}\ m}[/tex]

Δx = distance between central bright fringe and first bright fringe = 19.85 x 10⁻⁴ m = 1.985 mm

distance between central bright fringe and second dark fringe = 1.5Δx

distance between central bright fringe and second dark fringe = (1.5)(1.985 mm)

distance between central bright fringe and second dark fringe = 2.978 mm

An inventor makes a clock using a brass rod and a heavy mass as a pendulum. when the clock gets colder then the time clock would gain time

The expansion of any material due to the variation of the temperature is known as thermal expansion. It varied differently for different materials according to their corresponding values of the coefficient of the thermal expansion.

As given in the problem statement that an inventor makes a clock using a brass rod and a heavy mass as a pendulum, when the clock gets colder then the length of the brass decreases due to thermal expansion.

The length of the pendulum gets reduced which further results in the reduction in the time period, as per the formula of the time period for the pendulum

T = 2π√(L/g)

As the length of the brass gets reduced. This means the pendulum of the clock moves faster and the clock would gain time

Thus, if a  pendulum made of a heavy mass and a brass rod is used to create a clock by an inventor. The time clock would advance in time as the clock get colder

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Answer:

In winter, the temperature of the water is very low which makes the soap dissolve in a very small amount. ... Since the water molecules move faster, they come in contact with soap more often causing it to dissolve faster

Hope it helps...

Have a great day : )

Explanation:

Given that,

The mass of rock, m = 2.35-kg

It was released from rest at a height of 21.4 m.

(a) The kinetic energy is given by : [tex]E_k=\dfrac{1}{2}mv^2[/tex]

As the rock was at rest initially, it means, its kinetic energy is equal to 0.

(b) The gravitational potential energy is given by : [tex]E_p=mgh[/tex]

It can be calculated as :

[tex]E_p=2.35\times 9.8\times 21.4\\\\E_p=492.84\ J[/tex]

(c) The mechanical energy is equal to the sum of kinetic and potential energy such that,

M = 0 J + 492.84 J

M = 492.84 J

Hence, this is the required solution.

Answer:

When you add energy to a substance?

One change of state happens when you add energy to the substance. This change of state is called melting. By adding energy to the molecules in a solid the molecules begin to move quicker and can break away from the other molecules. The temperature at which a substance goes from a solid to a liquid is it melting point.

When you remove energy from a substance?

When a substance is heated, it gains thermal energy. Therefore, its particles move faster and its temperature rises. When a substance is cooled, it loses thermal energy, which causes its particles to move more slowly and its temperature to drop.

Explanation:

The addition of energy increases the kinetic energy of the particles, which reduces the intermolecular forces between the particles. Freezing occurs when a liquid becomes a solid and energy is released.

Atoms lose energy when they change from solid to liquid or gas and quid to gas.

Answer:

141.18 ohms

Explanation:

From the question given above, the following data were obtained:

Voltage (V) = 12

Current (I) = 0.085 A

Resistance (R) =?

The resistance needed can be obtained as follow:

V = IR

12 = 0.085 × R

Divide both side by 0.085

R = 12 / 0.085

R = 141.18 ohms

Therefore, a resistor of resistance 141.18 ohms is needed.

Answer:  Temperature in Fahrenheit is 577.4

Explanation:

The conversion factor for converting celcius to Fahrenheit is:

[tex]F=\frac{9}{5}\times C+32[/tex]

where F = temperature in Fahrenheit

C = Temperature in Celcius

Given : Temperature difference in Celcius = [tex]303^0C[/tex]

Putting in the values we get:

[tex]F=\frac{9}{5}\times 303+32[/tex]

[tex]F=577.4[/tex]

Thus the answer in Fahrenheit is 577.4

The required conversion of temperature from Celsius to Fahrenheit is 577.4 Degree Fahrenheit.

Given data:

The temperature difference between the inside and outside of a typical cryogenic pump is, [tex]\Delta T=303^{\circ}\rm C[/tex].

The degree measure of the flow of heat from one point to another is known as the temperature at a specific point. The temperature measurements are done in Celsius, Fahrenheit and Kelvin scales. The expression to convert the Celsius scale to Fahrenheit scale is,

[tex]T=(C \times \dfrac{9}{5} + 32)\;\rm ^{\circ}F[/tex]

Solving as,

[tex]T=(303 \times \dfrac{9}{5}+32 )\;\rm ^{\circ}F\\\\T=(303 \times \dfrac{9}{5}+32 )\;\rm ^{\circ}F\\\\T=577.4\;\rm ^{\circ}F[/tex]

Thus, we can conclude that the required conversion of temperature from Celsius to Fahrenheit is 577.4 Degree Fahrenheit.

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Answer:

see that the correct one is B

Explanation:

To solve this exercise let us use the kinematic relations

           v² = v₀² - 2 a x

as they indicate that the car stops, therefore the final speed is yield v = 0

          x = v₀² / 2a

let's calculate

          x = 2²/(2 0.8)

         x = 2.5 m / s²

When reviewing the answers we see that the correct one is B

?.............................

Kinetic energy decreases if either the mass or the velocity of the object decreases or if both decrease. and  Kinetic energy increases if either the mass or the velocity of the object increases or if both increase.

Explanation:

These statements explain the relationship between mass, velocity, and kinetic energy .i.e KE = ½mv², (3) Kinetic energy decreases if either the mass or the velocity of the object decreases or if b decrease. (4)Kinetic energy increases if either the mass or the velocity of the object decreases or if both decrease.

When a body has a mass of m kg and travels a velocity of v m/s then the kinetic energy is given by,

KE=1/2mv²

In the above relation, it is clearly shown that,

Kinetic energy is directly proportional to the mass of the body,

i.e

KE∝m

and also Kinetic energy directly varies with the square of the velocity of the body.

I.e

KE∝v²

Therefore, From the given expression we can conclude that when mass and velocity increased either one of them or both, the kinetic energy also gets increased.

And when mass and velocity decreased either one of them or both, the kinetic energy also gets decreased. Hence options (3) and (4) are correct.

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Answer:

my c-ock and balls be rotating im gunna be hxrny all day every day im gunna f-u-ck u and r-ape ur family girls should go back to the kitchen and hope not to be beat by their husband uh yea mhm girls desurve to be r-aped f-u-ck buck suck c-u-ck

Explanation:

Answer:

3.75

Explanati

Rhodium (Rh) is in period 5 on the periodic table. What does this tell you about this element ?

option - D

It has 5 energy levels/shells in its electron cloud.

With the information from the periodic table we can find that the correct statement is:

D. it is 5 energy level

The periodic table of the elements is a method of classifying the chemical elements based on their atomic number, it is divided into rows and columns

The rows are called the period and indicate the energy shell that is filled with electrons, all periods start with one electron and end when the shell is filled with 8 electrons.

The columns called groups correspond to elements that have the same number of electrons in their last shell, the chemical properties of the elements of the group are similar.

In this case we have an element the Rhodium, from period 5 and group VIIIB, when reviewing the period table it can be indicated that it has properties similar to cobalt and the inner layer is filled with two electors in its last layer.

When reviewing the different claims

a) False. The periodic table is not about molecules but about atoms

b) False. The metallic characteristics depend on the relationship between the number of electrons and the fermi level that is not indicated in the periodic table.

c) False. The number of protons is equal to the atomic number, in this case the rhodium has Z = 45, therefore it has 45 protons in the nucleus

d) True. It is at level 5 since the energy levels and the periods coincide.

In conclusion, with the information from the periodic table, we can find that the correct statement is:

D.  it is 5 energy level

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Answer:

the energy in the oscillations between the blocks is 3.025 J

Explanation:

Given the data in the question;

Force f = 138 N

stiffness of spring k = 605 kg/s²

mass of block = 202 g = 0.202 kg

pushing the block a distance 15 cm, the rightmost block has moved a distance 5 cm

i.e

x₁ = 15 cm

x₂ = 5cm

the energy in the oscillations between the blocks will be;

E[tex]_A[/tex] = E[tex]_B[/tex] = [tex]\frac{1}{2}[/tex]k( Δx )²

we substitute

= [tex]\frac{1}{2}[/tex] × k( 15 - 5 )² × 10⁻⁴

= [tex]\frac{1}{2}[/tex] × 605 × ( 10 )² × 10⁻⁴

= [tex]\frac{1}{2}[/tex] × 605 × 100 × 10⁻⁴

= 3.025 J

Therefore, the energy in the oscillations between the blocks is 3.025 J

Answer: Hello, Mark me as Brainliest! :)

If soldiers march across the bridge with a cadence equal to the bridge's natural frequency and impart $$1.00 × 10^4 J$$ of energy each second, how long does it take for the bridge's oscillations to go from 0.100 m to 0.500 m amplitude. $ 5 \times 10^7 \text{J} $ . \\ b) $ 12 \times 10^4 \text{s}$ .

Your Welcome!

Explanation:

Answer:

the waves in the sea,  leaves of the trees, cables in the bridges, pendulum clock

Explanation:

In nature there are many examples of simple harmonic motion, for example.

* The movement of the waves in the sea is an oscillation movement up and down

* The movement of the leaves of the trees when a wind blows and then stops, but the leaf and branches are oscillating

* The movement of the cables in the bridges, especially in the suspension bridges

* The movement of a pendulum clock

Answer:

a)    σ = [tex]\frac{Q_1}{ a^2 - b^2}[/tex] ,  b)  σ = [tex]\frac{Q_2}{d^2}[/tex] , c) Q_ {total} = Q₁ + Q₂,  σ_ {net} = [tex]\frac{Q_1 + Q_2}{\pi \ a^2}[/tex]

Explanation:

a) The very useful concept of charge density is defined by

          σ = Q / A

In this case we have a circular disk

The are of a circle is

         A = π r²

in this case we have a hole in the center of radius r = b, so

         A_net = π r² - π r_ {hollow} ²

         A_ {net} = π (a² - b²)

whereby the density is

          σ = [tex]\frac{Q_1}{ a^2 - b^2}[/tex]

b) The density of the other disk is

          σ = Q₂ / A₂

          σ = [tex]\frac{Q_2}{d^2}[/tex]

c) The total waxed load is requested by the larger circle

           Q_ {total} = Q₁ + Q₂

the net charge density, in the whole system is

          σ = [tex]\frac{Q_{total} }{ A_{total} }[/tex]

the area  is

          A_{total} = π a²

since the other circle is inside, we are ignoring the space between the two circles

          σ_ {net} = [tex]\frac{Q_1 + Q_2}{\pi \ a^2}[/tex]

Answer:

a. True

Explanation:

Sound are mechanical waves that are highly dependent on matter for their propagation and transmission.

Sound travels faster through solids than it does through either liquids or gases. A student could verify this statement by measuring the time required for sound to travel a set distance through a solid, a liquid, and a gas.

Mathematically, the speed of a sound is given by the formula:

[tex] Speed = wavelength * frequency [/tex]

Generally, the frequency of a sound wave determines the pitch of the sound that would be heard.

Diffraction occurs for all types of waves, including sound waves.

Answer: North East

Explanation: Trust me, I was just doing this on the Ck-12 and this the answer I choose and It said I'm correct.

Answer:

Gravity pulls down on the ball at g=-9.81 m/s^2. Up is positive, down is negative. The ball started at a certain initial velocity of Vi m/s. Time it took is t=4s. Final velocity is Vf=0 m/s, because at the highest point the ball stops moving.

Answer:

it should be changes in velocity

Explanation:

I hope this helps!

Answer:

true

Explanation:

force or powerbecause he pushes a disk

Answer:

athletic

Explanation:

because internet system has been down since we were in few days

Answer:

83.09 J

Explanation:

The potential energy at the point of the top of the jump is represented by the equation

[tex]mgdeltah[/tex]

when the dog jumps, all the potential energy converts to kinetic energy (1/2mv^2). Plugging in the values:

(7.7)(4.184)(1.1) = 83.0907 J