Một bóng đèn có hiệu điện thế định mức là 110V. Đặt vào hai đầu bóng đèn các hiệu điện thế sau đây, hỏi trường hợp nào dây tóc của đèn sẽ đứt?

Answer:

photosynthesis is the process by which green leaves prepare their food in the presence of sunlight,air and water

Explanation:

125 is your answer........

Answer:

Use the formula ∆H = m x s x ∆T to solve.

Explanation:

Once you have m, the mass of your reactants, s, the specific heat of your product, and ∆T, the temperature change from your reaction, you are prepared to find the enthalpy of reaction. Simply plug your values into the formula ∆H = m x s x ∆T and multiply to solve.

Answer:

sodium

Explanation:

it is highly reactive metal.

Answer:

aluminium

Explanation:

In a period , as we go from left to right in a periodic table, atomic number increases .

Differentiating electrons enters into same shell hence the effective nuclear charge decreases .

Hence atomic radius decreases along period.

Conculsion:

Aluminium is the element which has greater atomic radius and sulphur has smaller atomic radius.

Answer:

An artificial satellites revolves around the earth under the influence of its gravitational force. So it does not require any energy to revolve around energy.

or maybe god:)))(

we call it as well as 100 . so easey

Answer:

10 squared

Explanation:

10 squared

In Depth:

Let have a square that has a side length of 10.

A square four sides are equal and if we find the area of a squared, our formula is

[tex] {s}^{2} [/tex]

Our in this instance,

[tex] {10}^{2} [/tex]

or we call it

[tex]10 \: \: squared[/tex]

Answer:

1. 7.5 m

2. towards west side

explanation:

I hope it will help you

Answer:

cant see picture

Explanation:

Answer:

please add picture so i can help you

Explanation:

Answer:

The time required is 0.45 s.

Explanation:

Height, h = 1 m

initial velocity, u = m/s

Let the time is t.

Use second equation of motion

[tex]h = u t + 0.5 at^2\\\\1 = 0 +0.5 \times 9.8 \times t^2\\\\t = 0.45 s[/tex]

Answer:

A certain source of 12V with an internal resistance 1colomb is connected to 5colomb external resistance what is the current

Answer: The system of unit which is most convenient for use is the MKS unit.

Explanation:

System of units is defined as the complete set of units which comprises of both the fundamental units and the derived units. The mass, length and time are considered to be the fundamental quantities and their units are called the fundamental units. The systems of unit which are in common use can be compared through their description below:

--> MKS system of unit: In this system of unit, the unit of length is in meter (m). The unit if mass is in kilogram (k). The unit of time is in seconds (s). Hence the name m.k.s system of unit.

--> CGS system of unit: In this system of unit, the unit of length is in centimeter (cm). The unit if mass is in grams (g). The unit of time is in seconds (s). Hence the name c.g.s. system of unit.

--> FPS system of unit: In this system of unit, the unit of length is in foot (Ft). The unit if mass is in pound (Lb). The unit of time is in seconds (s). Hence the name m.k.s system of unit.

The system of unit which is most CONVENIENT for use is the MKS unit. This is because of the introduction of the international system of units (S.I unit). This unit was endorsed by the International Standard Organisation (ISO) to form a logical and interconnected framework for all measurements in science and technology. The MKS system of unit was made the SI units enabling physical quantities to be represented by only one unit.

Answer:

Explanation:

We need to find the x-components of each of these vectors and then add them together, then we need to find the y-components of these vectors and then add them together. Let's get to that point first. That's hard enough for step 1, dontcha think?

The x-components are found by multiplying the magnitude of the vectors by the cosine of their respective angles, while the y components are found by multiplying the magnitude of the vectors by the sine of their respective angles.

Let's do the x-components for all the vectors first, so we get the x-component of the resultant vector:

[tex]F_{1x}=12 cos0[/tex] and

[tex]F_{1x}=12[/tex]

[tex]F_{2x}=9cos90[/tex] and

[tex]F_{2x}=0[/tex]

[tex]F_{3x}=15 cos126.87[/tex] and

[tex]F_{3x}=-9.0[/tex]  (the angle of 126.87 is found by subtracting the 53.13 from 180, since angles are to be measured from the positive axis in a counterclockwise fashion).

That means that the x-component of the resultant vector, R, is 3.0

Now for the y-components:

[tex]F_{1y}=12sin0[/tex] and

[tex]F_{1y}=0[/tex]

[tex]F_{2y}=9sin90[/tex] and

[tex]F_{2y}=9[/tex]

[tex]F_{3y}=15sin126.87[/tex] and

[tex]F_{3y}=12[/tex]

That means that the y-component of the resultant vector, R, is 21.

Put them together in this way to find the resultant magnitude:

[tex]R_{mag}=\sqrt{(3.0)^2+(21)^2}[/tex] which gives us

[tex]R_{mag}=21[/tex] and now for the angle. Since both the x and y components of the resultant vector are positive, our angle will be where the x and y values are both positive in the x/y coordinate plane, which is Q1.

The angle, then:

[tex]tan^{-1}(\frac{21}{3.0})=82[/tex] degrees, and since we are QI, we do not add anything to this angle to maintain its accuracy.

To sum up: The resultant vector has a magnitude of 21 N at 82°

Answer:

They transform energy

Explanation:

thermodynamics deals with transfers of energy from one place to another and from one form to another and it's also deal with the relationship between heat and other forms of energy

Answer:

c

Explanation:

Answer:

Covalent bond.

Explanation:

There are 4 main types of bonds:

Covalent, ionic, metallic, and hydrogen.

Covalent bond: Involves the sharing of pairs of electrons, here the difference between the electronegativity of the atoms is not too large. Covalent bonds usually form an octet of electrons.

Ionic bond: This happens because the electrostatic attraction between the atoms whit very different electronegativities

Hydrogen bond: Electrostatic attractive force between an electronegative atom and a hydrogen atom covalently bonded to another electronegative atom.

Metallic bond: Type of bond that makes the metallic atoms to stay really tightly together. The atoms bond because of the electrostatic atractive force between conduction electrons and positively charged metal ions.

Now, in this case, we have the bond between Nitrogen (electronegativity = 2.0) and Hydrogen (electronegativity = 2.1)

So we can see that:

The elements are not metals, so we can discard metallic bond.

For a hydrogen bond, we need 3 atoms (one of which is hydrogen), here we have two, so we can discard this option.

Ionic bond needs different electronegativities, here the electronegativities are really close together, so the ionic bond can be discarded.

we can conclude that the bond will be a covalent bond.

Answer:

Increasing

Explanation:

I Hope it Helps

Let west be the negative direction, and east be positive. Then the total momentum of the system is conserved such that

(3.00 kg) (-2.00 m/s) + m (1.50 m/s) = 0

Solve for m :

m = (3.00 kg) (2.00 m/s) / (1.50 m/s) = 4.00 kg

Answer:

2min

Explanation:

i think it will be clear from photo

Answer: The formula for current is charge/time

so here we have to change subject so we are asked to look for time  

Explanation: so it would be T=Q/I

T=4/2

T=2s

hope this helpss

Explanation:

→ Volume of cone = πr² × h/3

Here,

→ Volume of cone = π(13)² × 27/3 cm³

→ Volume of cone = 169π × 9 cm³

→ Volume of cone = 1521π cm³

→ Volume of cone = 1521 × 22/7 cm³

→ Volume of cone = 33462/7 cm³

→ Volume of cone = 4780.28 cm³

Answer:

4,778.4 is correct

Explanation:

Answer:

New force = 0.063 N

Explanation:

Given that,

The electric force between two charges is[tex]4.2\times 10^{-2}\ N[/tex]

The formula for the electric force is:

[tex]F=\dfrac{kq_1q_2}{r^2}[/tex]

If the distance between the charges is doubled, r' = 2r and one of the charges is tripled, q₁' = 2q₁, q₂' = 3q₂

Put all the values,

[tex]F'=\dfrac{kq_1'q_2'}{r'^2}\\\\\dfrac{F}{F'}=\dfrac{\dfrac{kq_1q_2}{r^2}}{\dfrac{kq_1'q_2'}{r'^2}}\\\\\dfrac{F}{F'}=\dfrac{\dfrac{q_1\times q_2}{r^2}}{\dfrac{2q_1\times 3q_2}{(2r)^2}}\\\\\dfrac{F}{F'}=\dfrac{4}{6}=\dfrac{2}{3}\\\\F'=\dfrac{3\times 4.2\times 10^{-2}}{2}\\\\F'=0.063\ N[/tex]

So, the new force is 0.063 N.

Answer:

The force becomes 0.0315 N.

Explanation:

Force, F = 4.2 x 10^-2 N

When the distance is doubled, a charge is tripled, Let the force is F'.

The force between the two charges is

[tex]F = \frac{K qq'}{r^2}\\[/tex]

when, q' = 3 q' and r is 2 r so

[tex]F' = \frac{K 3qq'}{4r^2} = \frac{3 F}{4} = \frac {3\times 4.2\times 10^{-2}}{4}=0.0315 N[/tex]

Answer:

Correct option is C it decreases by a factor of 2

Answer: A - it increases by a factor of 4

Explanation:

Ohm's law is V = IR where V = potential difference, I = current, and R = resistance. Assuming that resistance stays constant (since the question mentioned no change in resistance), we only need to look at "V" and "I" in the equation V = IR.

"V" and "I" are directly proportional. In other words, whatever change happens to "V" will also occur to "I". Since "V" increases by a factor of 4, then "I" will also increase by a factor of 4.

You could also approach this problem by plugging in a change of 4 for the potential difference in the equation: V = I*R.

If we plug in 4V for V, we now have:

4V = I*R

Since the left side increases by a factor of 4, then the right side (only looking at current in this case) will also need to increase by a factor of 4 in order to have the right side stay equal to the left. Therefore, current will also increase by a factor of 4.

KE = (0.5) m v²

given that : v = speed of the bottle in each case = 4 m/s when m = 0.125 kg

KE = (0.5) m v² = (0.5) (0.125) (4)² = 1 J

when m = 0.250 kg KE = (0.5) m v² = (0.5) (0.250) (4)² = 2 J

when m = 0.375 kg KE = (0.5) m v² = (0.5) (0.375) (4)² = 3 J

when m = 0.0.500 kg KE = (0.5) m v² = (0.5) (0.500) (4)² = 4 J

Answer:

m=0.2kg=200g

Explanation:

F=2N, a=10m/s²

F=ma⇒ m=F/a=2/10=0.2kg=200g

Answer:

[tex]\boxed {\boxed {\sf 200 \ grams}}[/tex]

Explanation:

According to Newton's Second Law of Motion, force is the product of mass and acceleration.

[tex]F=m*a[/tex]

The force is 2 Newtons and the acceleration is 10 meters per square second. First, we should convert the units of Newtons to make unit cancellation easier. 1 Newton is equal to 1 kilogram meter per second squared. The force of 2 N equals 2 kg*m/s²

Substitute the known values into the formula.

[tex]2 \ kg*m/s^2 = m * 10 \ m/s^2[/tex]

We are solving for the mass, so we must isolate the variable m. It is being multiplied by 10 meters were second squared. The inverse of multiplication is division. Divide both sides by 10 m/s².

[tex]\frac { 2 \ kg *m/s^2}{10 \ m/s^2}=\frac{ m* 10 m/s^2}{10 \ m/s^2}[/tex]

[tex]\frac { 2 \ kg *m/s^2}{10 \ m/s^2}= m[/tex]

The units of meters per second squared cancel.

[tex]\frac { 2 \ kg}{10}= m[/tex]

[tex]0.2 \ kg =m[/tex]

Now, we must convert the mass to grams. There are 1000 grams in 1 kilogram. We can multiply the mass by 1000 or set up a ratio.

[tex]0.2 \ kg * \frac{1000 \ g}{1 \ kg}= 0.2 * 1000 \ g = 200 \ g[/tex]

The toy car's mass is 200 grams.

Answer:

False.

Explanation:

Tensile strength should remain constant, regardless of thickness. For larger cross sections, it can slightly increase because the atoms in the center become more constricted and therefore less responsive to the applied stress.

Answer:

Tensile strength should remain constant, regardless of thickness. For larger cross sections, it can slightly increase because the atoms in the center become more constricted and therefore less responsive to the applied stress.FALSE

Answer:

The position is 8.18cm from the mirror.

Nature is b=virtual

Size is 1.82cm

Explanation:

Note that for a convex mirror, the image distance and the focal length are negative;

Given

Object height H0 = 4cm

object distance u = 18cm

Radius of curvature R = 30cm

Since f = R/2

f = 30/2

f = -15cm

Recall that:

[tex]\frac{1}{f} =\frac{1}{u}+ \frac{1}{v}\\\frac{1}{-15}=\frac{1}{18}+\frac{1}{v} \\\frac{1}{v} =\frac{1}{-15} -\frac{1}{18}\\ \frac{1}{v} = \frac{-18-15}{270}\\\frac{1}{v} = \frac{-33}{270}\\v=\frac{-270}{33}\\v=-8.18cm[/tex]

Since the image distance is negative, this shows that the image is a virtual image.

To get the size:

[tex]\frac{H_1}{H_0}=\frac{v}{u}\\\frac{H_1}{4}=\frac{8.18}{18}\\18H_i=32.72\\H_i=\frac{32.72}{18}\\H_i= 1.82cm[/tex]