3. A roller-coaster car is moving over the top of a hill. At the instant it is on the hill top, it has a kinetic energy of E and a gravitational potential
energy of 3E. When it coasts down to ground level, if total mechanical energy is conserved, what is the kinetic energy of the car on the ground?
(A) 4E (B) 3E (C) 2E (D) E

Answers

Answer 1

Answer:

The correct option is (b).

Explanation:

Given that,

At the top of the hill, the kinetic energy is E and the gravitational potential energy is 3E.

We need to find the kinetic energy of the car on the ground.

We know that,

Mechanical energy = kinetic energy + potential energy

According to the law of conservation of energy, the total mechanical energy is conserved.

It means, when it coasts down to ground level, the kinetic energy is same as that on the top of the hill. Hence, the required kinetic energy on the ground is equal to 3E.


Related Questions

Which statement MOST LIKELY describes what changes when moving downwards from fluorine to chlorine on the periodic table?

A) The classification changes from nonmetal to metal

B) The ionic charge of the elements changes from positive to negative

C) The number of valence electrons increase

D) The number of total electrons increase​

Answers

Answer:

B) The ionic charge of the elements changes from positive to negative

Explanation:

In the case when there is a moving towards downward direction from fluorine to chlorine on the periodic table so this represent that there are an ionic elements charge varies i.e. from positive to negative

Therefore as per the given situation the option b is correct

And, the rest of the options are wrong

Answer:

b

Explanation:

i took the test

A snowboarder travels 17 m [N], 25 m [S], then 33 m [N]. Choose the correct
statement about the snowboarder's motion *
A. The snowboarder has a larger distance travelled than displacement
B. The snowboarder has a larger displacement than distance travelled
C. The snowboarder has more inertia after the 25 m trip than after the 17 m trip
D. The snowboarder has constant acceleration

Answers

The best answer to go with is b

A German Shepherd takes 4 hours to cover a distance, if it travels at a speed of 36mph. What should be its speed to cover the same distance in 3 hours

Answers

Answer:

v₂ = 48 mph

Explanation:

We know that,

Speed = distance/time

A German Shepherd takes 4 hours to cover a distance, if it travels at a speed of 36mph.

We need to find the speed to cover the same distance in 3 hours.

[tex]\dfrac{v_1}{v_2}=\dfrac{t_2}{t_1}\\\\v_2=\dfrac{v_1t_1}{t_2}\\\\v_2=\dfrac{36\times 4}{3}\\\\v_2=48\ mph[/tex]

So, the new speed is 48 mph.

please I need help its timed-
Students in a science class observed that when a strip of magnesium (Mg) metal was placed in a test tube containing hydrochloric acid (HCl), the magnesium began to bubble as hydrogen gas and magnesium chloride are formed. Which of the following choices show both the correctly balanced equation and identify the type of reaction?


A.

Mg + 2HCl →2H2 + MgCl2 (single replacement)


B.

Mg + 2HCl →H2 + MgCl2 (single replacement)


C.

Mg + 2HCl →H2 + MgCl2 (synthesis)


D.

2Mg + HCl →H2 + 2MgCl2 (synthesis)

Answers

Answer:c i think

Explanation:

A. Mg + 2HCl →2H2 + MgCl2 (single replacement)

What is single replacement?

A single replacement reaction is a type of chemical reaction in which one element is replaced by another element from a compound. In a single replacement reaction, an element reacts with a compound to form a new compound, in which one of the elements has been replaced.

For example, in the reaction Mg + 2HCl → 2H2 + MgCl2, the magnesium reacts with the hydrochloric acid to form hydrogen gas and magnesium chloride, with the magnesium taking the place of hydrogen in the compound.

Learn more about single replacement, here:

https://brainly.com/question/392491

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The pressure at the bottom of a lake is 300 000 N/m2 more than at the surface of the lake. The lake is fresh water (density = 1000 kg/m3).

Answers

Answer:

h = 30.61 m

Explanation:

In this problem they indicate the pressure at the bottom of the lake and the density of the water, for which they must ask what is the depth of the lake.

The pressure is given by the expression

           P = [tex]P_{atm}[/tex] + rho g h

           P - P_{atm} = rho g h

       

The gauge pressure value is P- P_{atm} = 3 105 N / m²

          h = [tex]\frac{P - P_{atm}}{ \rho \ g}[/tex]

let's calculate

          h = [tex]\frac{3 \ 10^5}{1000 \ 9.8}[/tex]

          h = 30.61 m

A car's wheel has a rotational inertia of 2.0\,\text {kg} \cdot \text m^22.0kg⋅m 2 2, point, 0, start text, k, g, end text, dot, start text, m, end text, squared. The wheel initially has a counterclockwise angular speed of 6.0\,\dfrac{\text {rad}}{\text s}6.0 s rad ​ 6, point, 0, start fraction, start text, r, a, d, end text, divided by, start text, s, end text, end fraction, but has a constant clockwise torque of 15 \,\text N \cdot \text m15N⋅m15, start text, N, end text, dot, start text, m, end text applied for 4.0\,\text s4.0s4, point, 0, start text, s, end text.

Answers

Answer:

-48

Explanation:

Answer:

6.0

Explanation:

If this is the problem on Khan Academy, I had done this and this was the correct answer.


The amplitude of a paricular wave is 4.0 m. The crest to trough distance
would be...
1. 8.0 m
2. 2.0 m
3. 4.0 m
4. 16.0 m

Answers

Answer:

The crest to trough distance = 8 m

Explanation:

Given that,

The amplitude of a particular wave is 4.0 m.

We need to find the crest to trough distance.

We know that,

Amplitude = The distance from the base line to the crest or the the distance from the baseline to the trough.

It means,

Distance from crest to trough = 2(Amplitude)

= 2(4)

= 8 m

Hence, the crest to trough distance is equal to 8 m.

What is the momentum of a child on a wagon traveling at a velocity of 1.5
m/s if the combined mass of the child and the wagon is 225 kg?

Answers

Answer:

the momentum of the child is 337.5 kg.m/s

Explanation:

Given;

velocity of the wagon, v = 1.5 m/s

the combined mass of the child and the wagon, m = 225 kg

The momentum of the child is calculated as;

P = mv

substitute the given values of mass and velocity to determine the momentum,

P =  225 x 1.5

P = 337.5 kg.m/s

Therefore, the momentum of the child is 337.5 kg.m/s

what is an example of an applied force?

1. a push or pull
2. friction
3. normal force
4. gravity

Answers

If a person is pushing a desk across the room, then there is an applied force acting upon the object. The applied force is the force exerted on the desk by the person. ... For example, if a book is resting upon a surface, then the surface is exerting an upward force upon the book in order to support the weight of the book.

Can anyone explain
if knows​

Answers

Answer:

Sry I’m just trying to get my points :(

Explanation:

Better luck nest time I would help if I was smart enough but currently I’m as d u m b as a rock...

Answer:

hi

Explanation:

15 facts of conservation of energy

Answers

Answer:

Ello, estoy aquí para ayudar, pero hablo español con optimismo, comprenderá lo que estoy diciendo. Intentaré ayudarlo. Espero que tengas un buen dia <3

Explanation:

Plzz help! A stationary speed gun emits a
microwave beam at 2.41x1010 Hz. It
reflects off a pitched baseball and
returns 3190 Hz higher. What is the
speed of the baseball?
(Unit = m/s)

Answers

Answer:

The speed of the baseball is approximately 19.855 m/s

Explanation:

From the question, we have;

The frequency of the microwave beam emitted by the speed gun, f = 2.41 × 10¹⁰ Hz

The change in the frequency of the returning wave, Δf = +3190 Hz higher

The Doppler shift for the microwave frequency emitted by the speed gun which is then reflected back to the gun by the moving baseball is given by 2 shifts as follows;

 [tex]\dfrac{\Delta f}{f} = \dfrac{2 \cdot v_{baseball}}{c}[/tex]

[tex]\therefore{\Delta f}{} = \dfrac{2 \cdot v_{baseball}}{c} \times f[/tex]

Where;

Δf = The change in frequency observed, known as the beat frequency = 3190 Hz

[tex]v_{baseball}[/tex] = The speed of the baseball

c = The speed of light = 3.0 × 10⁸ m/s

f = The frequency of the microwave beam = 2.41 × 10¹⁰ Hz

By plugging in the values, we have;

[tex]\therefore{\Delta f} = 3190 \ Hz = \dfrac{2 \cdot v_{baseball}}{3.0 \times 10^8 \ m/s} \times 2.41 \times 10^{10} \ Hz[/tex]

[tex]v_{baseball} = \dfrac{3190 \ Hz \times 3.0 \times 10^8 \ m/s }{2.41 \times 10^{10} \ Hz \times 2} \approx 19.855 \ m/s[/tex]

The speed of the baseball, [tex]v_{baseball}[/tex] ≈ 19.855 m/s

This is an example of a ____________ resource using _______.


A'renewable;; wind

B'nonrenewable; wind

C;renewable; electricity

D;nonrenewable;electricity

Answers

Answer:

A

Explanation:

I guess but not sure cause wind is soemthing you can get back electricity is soemthing you can't

Uranus requires 84 years to circle the sun. Find uranus's average distance from the sun as multiple of earth's average distance from the sun

Answers

Answer:

Uranus’ distance from the Sun is 2.88 billion km. The exact number is 2,876,679,082 km. Want that number in miles? Uranus’ distance from the Sun is 1.79 billion miles.

Explanation:

Uranus's average distance from the sun as multiple of earth's average distance from the sun is 19.2 AU.

According to Kepler's third law, the square of the period of revolution of the planets is equal to the cube of their mean distance from the sun in astronomical units.  

Using this law;

T^2 = r^3

T = period of revolution = 84 years

r = distance = ?

r = 3√T^2

r =  3√( 84)^2

r = 19.2 AU

Learn more: https://brainly.com/question/8646601

In order to move a bag of dog food across a room that measures 8 meters in length, you apply 10 Newtons of force. How much work was done?

Answers

Answer:

80 joules of work

Explanation:

Use W=F·d

W=10N(8M)= 80 Joules

Which of the following statements best describe the frequency of a wave?
A. It tells the height of each wave that passes through a given amount of time
B. It tells the number of wave cycles that passes through a given amount of time.
C. It tells how fast or slow a wave is moving
D. It tells the length of each wave that passes through a given amount of time

Answers

Answer:

I believe the answer is B.

HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
A ball with a mass of .012 kg moving at 15.0 m/s collides with a second ball with a mass of 36 g
moving at 5.0 m/s. After the collision, the 12 g ball moves in the same direction at 6.0 m/s. What
is the resulting velocity of the 36 g ball?

Answers

Answer:

Final velocity of ball B V2 = 8 m/s

Explanation:

Given:

Mass of Ball A M1 = 12 gram

Mass of Ball B M2 = 36 gram

Initial velocity of ball A U1 = 15 m/s

Initial velocity of ball B U2 = 5 m/s

Final velocity of ball A V1 = 6 m/s

Find:

Final velocity of ball B V2

Computation:

Using conservation of momentum;

M1U1 + M2U2 = M1V1 + M2V2

(12)(15) + (36)(5) = (12)(6) + (36)(v2)

180 + 180 = 72 + (36)(v2)

Final velocity of ball B V2 = 8 m/s

acontainer is filled whith mercury to alevel of 10m whit water to alevel of 8m and whit oil to alevel of 5m the densities oil ,water and mercury are 0.8g/cm³,1g/cm³ and 13.6g/cm³ calculate the total pressure exerted by the liquids at the base​

Answers

Answer:

1450.4 KN[tex]m^{2}[/tex]

Explanation:

Pressure = ρhg

where: ρ is the density of the liquid, h is the height and g the force of gravity.

Total pressure exerted by the liquids at the base = Pressure of oil + Pressure of water + Pressure of mercury

So that,

i. Pressure of oil = ρhg

(ρ = 0.8 g/cm³ = 800 kg/m³)

                        = 800 x 5 x 9.8

                        = 39200

Pressure of oil = 39200 N[tex]m^{2}[/tex]

ii. Pressure of water = ρhg

(ρ = 1 g/cm³ = 1000 kg/m³)

                                      = 1000 x 8 x 9.8

                                     = 78400

Pressure of water = 78400 N[tex]m^{2}[/tex]

ii. Pressure of mercury = ρhg

(ρ = 13.6 g/cm³ = 13600 kg/m³)

                      = 13600 x 10 x 9.8

                      = 1332800

Pressure of mercury = 1332800 N[tex]m^{2}[/tex]

So that,

Total pressure exerted by the liquids at the base = 39200 + 78400 + 1332800

                                               = 1450400

                                               = 1450.4 KN[tex]m^{2}[/tex]

Total pressure exerted by the liquids at the base is 1450.4 KN[tex]m^{2}[/tex].

What is the reason for heat transfer from one substance to another?
OA. difference in pressure
OB.
difference in volume
O c.
difference in temperature
OD.
difference in mass

Answers

c difference in temperature

Answer:

A I think

Explanation:

heated air molecules have a lot if pressure and they try to release that pressure by either expanding or transfering

Discuss your theory on why the light bulbs in the combination circuit have
different brightness.

Answers

Answer:

The voltage drop across each resistance is the same as the applied one. Hence most of the supplied voltage (the electrical energy) reaches the bulb. Hence it glows brighter. Now in the case of series combination of resistors, the effective resistance of the circuit increases.

Explanation: Discuss your theory on why the light bulbs in the combination circuit have

different brightness.

Please help me I am desperate this is due now

Answers

Answer:

Distance travelled is 7 meters and the displacement is 3 meters

give person above or below brainliest

simplify and leave your answer with positive index
2^n-4×16^1+n
/
8^-n×4^-4n​

Answers

Answer:

2¹⁶ⁿ

Explanation:

2ⁿ¯⁴ × 16¹⁺ⁿ / 8¯ⁿ × 4¯⁴ⁿ

The above expression can be simplified as follow:

2ⁿ¯⁴ × 16¹⁺ⁿ / 8¯ⁿ × 4¯⁴ⁿ

Recall:

16 = 2⁴

8 = 2³

4 = 2²

Thus,

2ⁿ¯⁴ × 16¹⁺ⁿ / 8¯ⁿ × 4¯⁴ⁿ

= 2ⁿ¯⁴ × 2⁴⁽¹⁺ⁿ⁾ / 2³⁽¯ⁿ⁾ × 2²⁽¯⁴ⁿ⁾

= 2ⁿ¯⁴ × 2⁴⁺⁴ⁿ / 2¯³ⁿ × 2¯⁸ⁿ

Recall:

Mᵃ × Mᵇ = Mᵃ⁺ᵇ

2ⁿ¯⁴ × 2⁴⁺⁴ⁿ / 2¯³ⁿ × 2¯⁸ⁿ

= 2⁽ⁿ¯⁴⁾⁺⁽⁴⁺⁴ⁿ⁾ / 2¯³ⁿ⁺⁽¯⁸ⁿ⁾

= 2ⁿ¯⁴⁺⁴⁺⁴ⁿ/ 2¯³ⁿ¯⁸ⁿ

= 2⁵ⁿ / 2¯¹¹ⁿ

Recall:

Mᵃ / Mᵇ = Mᵃ¯ᵇ

2⁵ⁿ / 2¯¹¹ⁿ = 2⁵ⁿ¯⁽¯¹¹ⁿ⁾

2⁵ⁿ / 2¯¹¹ⁿ = 2⁵ⁿ⁺¹¹ⁿ

2⁵ⁿ / 2¯¹¹ⁿ = 2¹⁶ⁿ

Therefore,

2ⁿ¯⁴ × 16¹⁺ⁿ / 8¯ⁿ × 4¯⁴ⁿ = 2¹⁶ⁿ

A stationary 2 kg football is kicked by a footballer, the football moves off with a velocity of 5 m/s. If the footballer is in contact with the football for 0.5 s, what is the average force applied by the footballer
on the football?
Please helppp!!!!

Answers

Answer:

F = 20 N

Explanation:

Given that,

Mass of the football, m = 2 kg

Initial speed, u = 0

Final speed,v = 5 m/s

The time of contact, t = 0.5 s

We need to found the average force applied by the footballer  on the football. We can find it using the formula.

[tex]F=\dfrac{m(v-u)}{t}\\\\F=\dfrac{2\times (5-0)}{0.5}\\\\F=20\ N[/tex]

So, the required force is 20 N.

Answer:

F=20

Explanation:

f=20

what is the correct equation for calculating kinetic energy?

1. kinetic energy = potential energy - total energy
2. kinetic energy = total energy - potential energy
3. kinetic energy = 1/2 x (total energy + potential energy)
4. kinetic energy = potential + total energy

Answers

Answer:

2. kinetic energy = total energy - potential energy

Explanation:

The total energy of a system is the addition of kinetic and potential energy of the system. Kinetic energy can be regarded as form of energy posses by an object when it's in motion

Total energy = kinetic energy + potential energy

(If we make Kinectic energy the subject of the formula, we have)

kinetic energy = total energy - potential energy

What is used in a torch?
a. Dry cell
b. Secondary cell
c. Generator
d. Fuse

Answers

Answer:a.Dry cell

Explanation: A dry cell is a type of electric battery, commonly used for portable electrical devices like a flashlight

Answer:a.Dry cell

Explanation:

does sound waves move quicker through cold or warm matter

Answers

Answer:

Warm matter

Explanation:

Atoms in warm matter are more easily excitable - they jiggle and move more rapidly than atoms in a cold environment, and since a sound wave is a wave of vibrating matter, these waves will naturally travel quicker when it's warmer.

How is light different than mechanical waves?

Answers

Light waves don’t involve the motion of matter. Light waves are different from mechanical waves, because they can travel through a vacuum. Light waves are just one type of electromagnetic wave.

Can someone answer this multiple choice, and ignore the one I accidentally touched

Answers

Answer:

20N

Explanation:

Force= Mass*Acceleration

Force=10kg*2m/s^2

Force=20N

Answer:

20 N

Explanation:

Newton's Second Law of Motion gives us the relationship between force, mass, and acceleration:

F = ma  

In this problem, we are given the mass of the body and its acceleration.

m = 10 kg a = 2 m/s²

Substitute these values into the formula to find the force acting on the body.

F = (10 kg)(2 m/s²) F = 20 kg · m/s² F = 20 N

The units for force is in Newtons, so the answer is the second option.

The relationship between kinetic energy and speed is ________ proportional

Answers

The kinetic energy is proportional to the square of the speed, so doubling the speed increases the kinetic energy by a factor of 4.

The relationship between kinetic energy and speed is directly proportional.

The given problem is based on the Kinetic energy. The energy possessed by any object by virtue of its motion is known as kinetic energy of an object. The mathematical expression for the kinetic energy is given as,

[tex]KE = \dfrac{1}{2}mv^{2}[/tex]

Here,

m is the mass of object.

v is the speed of object.

the mass of any object remains constant. Then, the kinetic energy is given as,

[tex]KE \propto v^{2}[/tex]

Thus, we can conclude that the kinetic energy is directly proportional to the square of speed of object.

Learn more about the kinetic energy here:

https://brainly.com/question/17858145

Calculate the weight of a boy of mass 67kg on Earth if gravity = 10m/s/s.

Answers

So the equation for weight is mass*gravity. For this example I will use 9.81 and 10.
67*10=670N
67*9.81=657.27N
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What was the primary purpose of the Gadsden purchase? 96/45 = b/20 b = ?Please help me find the value of b. Rita goes to the mall. If x is the number of items she bought, the expression 12.88x+28 gives the amount she spent in dollars at one store. Then she spent 21 dollars at another store. Find the expression which represents the amount Rita spent at the mall. Then estimate how much Rita spent if she bought 2 items . PLZZ HELPP I NEED TO TURN IT IN BY TOMORROW!!!!! How do they prepare themeselves for an emergency? My brain is gonna explode please help What are the possible values of x in the equation | x + 5 | = 4? In neighborhoods like Kibera in Nairobi, Kenya, many children go without education because of a lack of schools. Other children lose educational opportunities because their families can't afford to pay for classes. Using complete sentences, describe two consequences of a lack of education for city residents. What could happen to a city when many of its residents lose the opportunity to learn? slope from graph HELP ME PLS Al's rent-a-car offers a rate of $48each day or a weekly rate of $275.If you need the car for 7 days, which isthe better buy? What is the purpose of adapting a written text into a film?Select all that apply.A. to help enhance imagination and creativity B. to convey an interpretation with a unique style C. to visually communicate text-heavy content D .to appeal to a wider audience hat are the solutions of x squared + 6 x minus 6 = 10? We didn't know that getting a puppy would change our lives so much. I thought that having a puppy would be fun, but it endsup being a big responsibility. Someone has to change the puppy's water and feed her every day. Someone has to take heroutside every time she needs to "go potty" or clean up any potty accidents that happen if she doesn't go outside. Someonealso has to make sure she gets enough exercise each day.Which sentence provides the BEST conclusion to the paragraph? how would you caption this and why If the total length of all the meteors were distributed equally between each meteor, how long would each one be? one and one thirty sixth inches one and one thirty eighth inches one and one fortieth inches one and one forty second inches They say that smoking can reduce your life expectancy by 20%. If the life expectancy for a non-smoker is 90 years old, what is the life expectancy for a smoker? Mr. Jones sent his kids to Mt. Olympus. He gave each of his 5 children money for the day that included money for 4 drinks, 3 sandwiches, 2 treats, and $25 for the ticket in to the park.If drinks (d) cost $1.50, sandwiches (s) cost $2, treats (t) costs $1, What is the total amount of money Mr. Jones gave to all five of his children? NEED ANSWERS ASAP, THANKS!Employees at a store earned $275, $330, $290, $300, $350, $365, and $310 during one week. What measure of central tendency or range would make the salaries look the highest?What is the mean? what's the value of given expression[tex] \sqrt{21 + 79} [/tex] Which of the following quotes best supports the answer to Part A? i am very real I need help asap please Answer choices: (0, -1) , (0, 1) (-3, 0) (0, -2), (2, 0)(0, 3)questions: part a: identify the point that is an X intercept in order from left to right (1st, 2nd, 3rd, and 4th)part b: the y-intercept of the graph is