stella is driving down a steep hill. she should keep her car __________ to help _________.

Answer:

Train A has a speed 20 miles per hour greater than that of train B. If train A travels 300 miles in the same times train B travels 220 miles, what are the speeds of the two trains?

2. A woman has a total of $13,000 to invest. She invests part of the money in an account that pays 11% per year and the rest in an account that pays 12% per year. If the interest earned in the first year is $1490 how much did she invest in each account?

Explanation:

Answer:

11115 J

Hope you could get an idea from here.

Doubt clarification - use comment section.

Answer:

Assuming there are 28 days in each month,

750W = 0.75kW

Cost of electric bill = 0.75 × 8 × 28 × $0.23

                               = $38.64

Answer:

5 amps

Explanation:

I = P/V

I = current (amps)

P = power (watts)

V = voltage (volts)

I = 60/12

I = 5

Answer:

No acceleration. All of the forces are acting equally on the paper air plane therfore It isn't going to move any where.

Assuming both billiard balls have the same mass, conservation of momentum says

[tex]m\vec v_1 + m\vec v_2 = m{\vec v_1}\,' + m{\vec v_2}\,'[/tex]

where m = mass of both billiard balls, and v₁ and v₂ = their initial velocities, and v₁' and v₂' = their final velocities. The masses are the same so the exact value of m is irrelevant. The first ball has initial speed 5 m/s and the second is at rest, so

[tex]\left(5 \dfrac{\rm m}{\rm s}\right) \, \vec\imath = {\vec v_1}\,' + {\vec v_2}\,'[/tex]

After the collision, the first ball has speed 4.35 m/s and is moving at angle of 30° below the original path, so

[tex]{\vec v_1}\,' = \left(4.35\dfrac{\rm m}{\rm s}\right)\left(\cos(30^\circ) \, \vec\imath + \sin(30^\circ) \, \vec\jmath\right) \approx \left(3.77 \dfrac{\rm m}{\rm s}\right) \vec\imath + \left(-2.18 \dfrac{\rm m}{\rm s}\right) \vec\jmath[/tex]

Then the second ball has final velocity vector

[tex]{\vec v_2}\,' \approx \left(1.23 \dfrac{\rm m}{\rm s}\right) \vec\imath + \left(2.18 \dfrac{\rm m}{\rm s}\right) \vec\jmath[/tex]

so it moves with speed

[tex]\left\|{\vec v_2}\,'\right\| \approx \sqrt{\left(1.23\dfrac{\rm m}{\rm s}\right)^2 + \left(2.18\dfrac{\rm m}{\rm s}\right)^2} \approx \boxed{2.50 \dfrac{\rm m}{\rm s}}[/tex]

at an angle of

[tex]\theta \approx \tan^{-1}\left(\dfrac{2.18}{1.23}\right) \approx \boxed{60.5^\circ}[/tex]

or about 60.5° above the original line of motion.

Answer:

The speed.

Explanation:

The slope of a line is that line's rate of change.  If a car is travelling at 20 km/hr and we plot distance vs time graph, the slope of that line will be 20.

Answer:

The more mass an object has, the greater its gravitational field and gravity force will be.

Explanation:

gravity force = mass × gravitational field strength (g)

The more mass, the more g-force.

Answer:

Explanation:

The concept of a new strong nuclear force was introduced. In 1935, the first theory for this new force was developed by the Japanese physicist Hideki Yukawa, who suggested that the nucleons would exchange particles between each other and this mechanism would create the force.

Explanation:

For the first question look at the picture. It should be pretty clear. Remember that cos45° = sqrt2 / 2.

2) We calculate it thanks to the conservation of mechanical energy:

Em1 = Em2

U1 + K1 = U2 + K2

K1 = 0J

U2 = 0j

U1 = K2

3) mgh = 1/2mv^2

v = sqrt(2gh)

Answer:

42 Joules

Explanation:

Potential energy

= weight × height

= (3.5)(12)

= 42 joules

Answer:

>400N is needed to balance that lever

Answer:

The gravity helps the planets stay together near the Sun, without it Earth would be floating away with the planet eventually becoming frozen up, thus the role gravity have in the motion of planets around the sun is by keeping them together.

Explanation:

Hope this helps!

Answer:

Doubling the large mass

Explanation:

By doubling the mass you will get more gravational force

Answer:

explorer

Explanation:

Answer:

a) EXPLORER

Explanation:

An explorer is someone who travels to new places or does new things.

3. Distance is a quantity that is always a vector.

B.

Answer:

i think wave lengh not 100% sure tho

If the energy of the mechanical wave will increase or decrease, then the wavelength will also change accordingly. Hence, option A is correct.

The distance between two identical locations (adjacent crests) in successive cycles is known as the wavelength, and it is used to describe waveform signals that are transmitted over wires or into space. Typically, in wireless systems, this length is specified in meters (m), centimeters (cm), or millimeters (mm). The wavelength is more frequently described in nanometers (nm), which are units of 10⁻⁹ m, or angstroms, which are units of 10⁻¹⁰ m, for infrared (IR), visible light (UV), and gamma radiation.

Frequency, which is defined as the number of wave cycles per second, and wavelength have an inverse relationship. The wavelength of a signal decreases with increasing frequency, or we can say that wavelength and refractive index are inversely proportional to each other.

To know more about Wavelength:

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Answer:

because of the gravity of the earth

Answer:

3000N

Explanation:

divided to get answer

the force needed to accelerate the 1000kg car by 3m/s2 is 3000N

Answer:

Inside the film the wavelength will be λ/n

For constructive interference to occur the film must be λf/4 thick where λf is the wavelength of the light in the film - there will be a 180 degree phase shift at the water/film interface since the index of refraction of the film is greater than that of water - and the light has to travel λ/2 inside the film for constructive interference to occur

280 nm / 1.6 * 4 = 700 nm is the greatest wavelength allowed

Note that 700 nm is also the upper wavelength of the visible spectrum

Answer:

depth from optical expansion

Explanation:

Answer:

magnetic force

Explanation:

because iron is magnetic so magnet is able to attract iton

Answer:

C

Explanation:

A and B are not true and D is a disadvantage

Answer:

C.  Long-term cost savings for energy users.

Explanation:

C is correct because the first option is a drawback that is unlikely.  B is a good answer but not the best.  It's a likely benefit, but C is a more likely benefit.  D is a drawback.  C is correct.  I also got this right on my quiz.

Hope this helps!

The velocity of the pitcher at the given mass is 0.1 m/s.

The given parameters:

Let the velocity of the pitcher = u₁

Apply the principle of conservation of linear momentum to determine the velocity of the pitcher as shown below;

m₁u₁ = m₂u₂

[tex]u_1 = \frac{m_2 u_2}{m_1} \\\\u_1 = \frac{0.15 \times 35}{50} \\\\u_1 = 0.105 \ m/s\\\\u_1 \approx 0.1 \ m/s[/tex]

Thus, the velocity of the pitcher at the given mass is 0.1 m/s.

Learn more about conservation of linear momentum here: https://brainly.com/question/13589460

Answer:

1) Average velocities:

Given the magnitudes of 2 velocity vectors, in different time instants, the average velocity is defined as the difference of the 2 velocity magnitudes, in absolute value, divided by the interval of time occuring between the measurement of the velocity magnitudes.

2) Average acceleration

Given the magnitudes of 2 acceleration vectors, in different time instants, the average acceleration is defined as the difference of the 2 acceleration magnitudes, in absolute value, divided by the interval of time occuring between the measurement of the acceleration magnitudes.

As you see the definitions are pretty similar.

Note: I didn't copy-paste this answers from any other site.

Answer:

D.

Explanation:

it is indeed a representation of how the valence electrons in an element,coumpound, or ion are arranged.

to ensure you i was just quized on this and D is the correct anwser

A representation of the arrangement of valence electrons in an element, compound, or ion -  statement most completely describes a Lewis electron dot diagram. Hence, option (D) is correct.

If the compound's molecular formula is known, electron dot structures or Lewis dot formulas can be drawn.

It describes the type of bond and the placement of the atoms within the molecule that are joined together. In honor of American chemist Gilbert Newton Lewis, molecules are depicted as having a Lewis electron dot structure or simply a Lewis structure.

Lewis dot structures, also known as electron dot structures, are schematics that show the interatomic chemical bonds in a molecule. Additionally, they show how many lone pairs there are overall in each of the atoms that make up the molecule. Common names for Lewis dot structures include electron dot structures and Lewis structures. Lewis described an acid as an electron pair acceptor, while a base is an electron pair giver.

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Answer:

Atom, the cross-platform, open source code editor developed by Github, has become quite popular thanks to its plug-ins and embedded Git Control. ... There are, however, official Atom repositories for some Linux distributions, like Ubuntu, Debian, Fedora, Red Hat, CentOS, and open.

Answer: b. equal to or the same

In Law of Conservation of mass,  the mass of the product equals the mass of the reactant. A reactant is the chemical reaction of two or more elements to make a new substance, and a product is the substance that is formed as the result of a chemical reaction.

pls mark brainliest! i really need one :(