Do only number 3 and thank

Answer:

[tex] |B| = \sqrt{ {B _{x} }^{2} + {B _{y} }^{2} } \\ = \sqrt{ {7}^{2} + {5}^{2} } \\ = \sqrt{74} \\ = 8.6[/tex]

[tex]let \: the \: angle \: be \: \theta \\ \tan(\theta) = \frac{B _{y} }{B _{x} } \\ \tan( \theta) = \frac{ - 5}{7} \\ \theta = { \tan }^{ - 1} ( \frac{ - 5}{7} ) \\ = 35.5 \degree[/tex]

Answer:

A.

Explanation:

I think it might be the big number A

Answer:

can you clear your question I can't understand

4E

The elastic potential energy of an elastic material (e.g a spring, a wire), is the energy stored when the material is stretched or compressed. It is given by

U = [tex]\frac{1}{2}kx^2[/tex]               --------------------(i)

Where;

U = potential energy stored

k = spring constant of the material

x = elongation (extension or compression of the material).

From the first statement;

when elongation (x) is 4cm, energy stored (U) is E

Substitute these values into equation (i) as follows;

E = [tex]\frac{1}{2}k(4)^2[/tex]

E = 8k

Make k subject of the formula    

k = [tex]\frac{E}{8}[/tex]   [measured in J/cm]

From the second statement;

It is stretched by 4cm.

This means that total elongation will be 4cm + 4cm = 8cm.

The potential energy stored will be found by substituting the value of x = 8cm and k = [tex]\frac{E}{8}[/tex] into equation (i) as follows;

U = [tex]\frac{1}{2}\frac{E}{8} (8)^2[/tex]  

U = [tex]\frac{1}{2}{8E}[/tex]

U = [tex]{4E}[/tex]

Therefore, the potential energy stored will now be 4 times the original one.

The kinetic energy of the rocket should be A. it doubles.

Kinetic energy represents the energy where an object or a particle should be the reason for its motion. It transfers energy than it should be done on an object by applying a net force, so the object speeds up and thereby gains kinetic energy. In the case when the speed increased to 2v so the kinetic energy should also doubles.

Learn more about speed here: https://brainly.com/question/17052831

Answer:

nice calculations!

Explanation:

Complete question:

(b) How much energy must be supplied to boil 2kg of water? providing that the specific latent heat of vaporization of water is 330 kJ/kg. The initial temperature of the water is 20 ⁰C

Answer:

The energy that must be supplied to boil the given mass of the water is 672,000 J

Explanation:

Given;

mass of water, m = 2 kg

heat of vaporization of water, L =  330 kJ/kg

initial temperature of water, t = 20 ⁰C

specific heat capacity of water, c = 4200 J/kg⁰C

Assuming no mass of the water is lost through vaporization, the energy needed to boil the given water is calculated as;

Q = mc(100 - 20)

Q = 2 x 4200 x (80)  

Q = 672,000 J

Q = 672,000 J

Q = 672,000 J

Therefore, the energy that must be supplied to boil the given mass of the water is 672,000 J

Answer:

v = 10.09 m / s,   8.78 North of East

Explanation:

The easiest way to solve this exercise is to decompose the velocities into a coordinate system, where the x-axis coincides with the West-East direction and the y-axis coincides with the South-North direction.

athlete's velocity v₁ₓ = 3 m / s

wind speed 2 v₂ = 10 m / s with direction 65 north of east

          sin 65 = v_{2y} / v₂

          cos 65 = v₂ₓ / v₂

          v_{2y} = v₂ sin 65

          v₂ₓ = v₂ cos 65

          v_{2y} = 10 sin 65 = 9.06 m / s

          v₂ₓ = 10 cos 65 = 4.23 m / s

wind speed 3 v₃ = 8 m / s with direction 70 south of east

This angle measured from the positive side of the x-axis is

          θ = 360 - 70

          θ = 290

          sin 290 = v_{3y} / v₃

          cos 290 = v₃ₓ / v₃

          v_{3y} = v₃ sin 290

          v₃ₓ = v₃ cos 290

           v_{3y} = 8 sin 290 = -7.52 m / s

          v₃ₓ = 8 cos 290 = 2.74 m / s

now we can find each component of the velocity

X axis

        vₓ = v₁ + v₂ₓ + v₃ₓ

        vₓ = 3 + 4.23 + 2.74

        vₓ = 9.97 m / s

Y axis  

        v_y = v_{2y} + v_{3y}

        v_y = 9.06 - 7.52

         v_y = 1.54 m / s

to find the modulus let's use the Pythagorean theorem

         v = [tex]\sqrt{v_x^2 + v_y^2 }[/tex]

         v = [tex]\sqrt{9.97^2 + 1.54^2}[/tex]

         v = 10.09 m / s

let's use trigonometry for the direction

         tan θ = v_y / vₓ

        θ = tan⁻¹ v_y / vₓ

        θ = tan-1 1.54 / 9/97

         θ = 8.78

the address is 8.78 North of East

Explanation:

ahhh, maybe you mean , what happens when a light ray hits the interface of two media perpendicular to the normal.

if that is the case then the light ray will not bend but it will travel in the same direction in the second medium as it was travelling in it's first medium

hope this helps bro

Answer:

67 kPa

Explanation:

Given that,

Initial volume, V₁ = 25 cm³

Initial pressure, P₁ = 100 kPa

Final volume, V₂ = 15 cm³

We need to find the change in pressure of the gas. The relation between the volume and pressure of a gas is given by :

[tex]P\propto \dfrac{1}{V}\\\\\dfrac{P_1}{P_2}=\dfrac{V_2}{V_1}\\\\P_2=\dfrac{P_1V_1}{V_2}\\\\P_2=\dfrac{100\times 25}{15}\\\\=166.66\ kPa[/tex]

or

= 167 kPa

The change in pressure,

= P₂ - P₁

= 167 kPa - 100 kPa

= 67 kPa

Hence, the correct option is (a).

Answer:

its two valence electrons

Explanation:

Calcium is a group 2 element with two valence electrons. Therefore, it is very reactive and gives up electrons in chemical reactions.

UR WELCOME!! :)

Answer:

Density = 4.84 g/cm³

Explanation:

Given the following data;

Mass = 30 g

Volume = 6.2 cm³

To find the density of the piece of iron;

Density can be defined as mass all over the volume of an object.

Simply stated, density is mass per unit volume of an object.

Mathematically, density is given by the equation;

[tex]Density = \frac{mass}{volume}[/tex]

Substituting into the equation, we have;

[tex]Density = \frac{30}{6.2}[/tex]

Density = 4.84 g/cm³

Answer:

The eddy currents will be very small.

Explanation:

An object made of several thin conducting layers separated by insulation may not be affected by magnetic damping because the eddy current produced in each layer due to induction will be very small and the opposing magnetic flux produced by the eddy currents will be very small.

Answer:

c they obey inverse square law

Answer:

194 degrees farenheit! hot

Explanation:

(90°C × 9/5) + 32 = 194°F

Answer:

194

Explanation:

to get from celcius to Fahrenheit

multiply temperature by 2 and add 30

Answer:

ml tayo 1v1 durugin kita

Explanation:

ano takot ml 1v1

Answer:

334.314 (kJ)

Explanation:

1) the formula for the required energy is: Q=c*m(Bp-t), where c - 4100 J/kg*C; m - 0.9 kg; Bp - 100.6 C; t - 10 C.

2) according to the formula above:

Q=4100*0.9*(100.6-10)=41*9*906=334314 (J).

Answer:

Explanation:

Since this is not parabolic motion, it is one-dimensional motion. Very simple. What we are given is

mass: 15.0 kg

initial velocity: 2.0 m/s

acceleration: .75 m/s/s

time: 6.0 seconds

Since we are looking for final velocity, the equation we need for this is

v = v0 + at that says final velocity is equal to the initial velocity plus the acceleration of the object times how long it travels. We don't have a need for the mass here at all.

[tex]v=2.0\frac{m}{s}+.75\frac{m}{s^2}(6.0s)[/tex]

Notice that one of the seconds labels to the right of the plus sign cancel out, leaving us with like units...which we HAVE to have if we want to add.

Simplifying a bit gives us

v = 2.0 m/s + 4.5 m/s so

v = 6.5 m/s

Answer:

E = 25 J

Explanation:

Given that,

Spring constant, k = 200

Compression, x = 0.5

We need to find the potential energy stored in the spring. The formula for the stored potential energy in the spring is given by :

[tex]E=\dfrac{1}{2}kx^2[/tex]

Put all the values,

[tex]E=\dfrac{1}{2}\times 200\times 0.5^2\\\\E=25\ J[/tex]

So, 25 J of potential enersy is stored in the spring.

Answer: Create a hypothesis

Explanation:

From the information given, information has been gathered and the identification to ascertain if there's a change. Then, an hypothesis has to be created in order to know what the problem is.

One has to carry out some research in order to know what went wrong and should also validate the hypothesis by consulting with ones peers. By doing this, the most likely causes of the issues will be gotten.

Answer:

1. less. 2 greater. 3. the same. 8. An FM radio station broadcasts its signal at a fre​- ... wave 3. | 3x108 = 269.15x107). = 3.20m. 2. An electromagnetic AM-band radio wave could have Base your answers to questions 9 and 10 on the informa- ... X rays. -Microwaves. -Long

Answer:

m=6.25kg

Explanation:

Force= mass × acceleration

50=m×8

make m subject of the formula...

m=50/8

m=6.25kg

Answer:

[tex]\boxed {\boxed {\sf 6.25 \ kilograms}}[/tex]

Explanation:

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

[tex]F= m \times a[/tex]

We know the force is 50 Newtons and the acceleration is 8 meters per second squared. Let's convert the units to make the problem and unit cancellation easier.

1 Newton is equal to 1 kilogram meter per square second (1 kg*m/s²), so the force of 50 N is equal to 50 kg*m/s².

Now we know 2 values:

Substitute the values into the formula.

[tex]50 \ kg *m/s^2= m \times 8 \ m/s^2[/tex]

Since we are solving for the mass, we must isolate the variable, m. It is being multiplied by 8 meters per square second and the inverse of multiplication is division. Divide both sides by 8 m/s².

[tex]\frac {50 \ kg *m/s^2}{8 \ m/s^2}= \frac{m \times 8 \ m/s^2}{8 \ m/s^2}[/tex]

[tex]\frac {50 \ kg *m/s^2}{8 \ m/s^2}= m[/tex]

The units of meters per square second (m/s²) cancel.

[tex]\frac {50 \ kg }{8 }=m[/tex]

[tex]6.25 \ kg =m[/tex]

The mass is 6.25 kilograms.

Answer:

new PE at top=original PE - energy lost

mgh=.2(9.8)20-30

Explanation:

mgh=.2(9.8)20-30 = 9.2

Answer:

.04 kg m/s

Explanation:

Momentum is simply mass multiplied by velocity given by p = mv. You can consider momentum as mass in motion.

Before the collision, the data given for the toy train:

v = 0.5m/s

m = 75g

We need to convert grams into the SI unit of mass, kg.

75g / 1000g * 1kg = 0.075kg

Using p = mv, we can determine:

p = 0.075kg * 0.5m/s = 0.0375 kg m/s

Rounding to the value of 1 sig-fig, it comes out to be 0.04 kg m/s.

Answer:

Middle layer, density increases with depth as pressure increases

Explanation:

The Earth's mantle is the middle layer of the earth. It is the largest layer of the earth consisting of about 83 % of the earth's volume and continues to a depth of 2900 km. Also, the mantle is hot and made of solid rock. It is hot since it is close to the core and its pressure and density increases with depth causing it to be more solid.

So, the Earth's mantle is the middle layer, density increases with depth as pressure increases.

Answer:

(I'm not 100% sure about this)

Maybe its because the soccer ball is faulty. Such troublemakers can include holes in the ball, preventing it from inflating.

Answer:

We can reasonably improve a machines ability to do work by reducing the friction between the moving parts of machine.

Explanation:

According to the law of conservation of energy, the energy can neither be created nor destroyed.

Answer:

sum of the two forces as both point to the right is a force that points to the right,

Explanation:

The force on the cast load at point Y is given by

        F = q_y  E

force is a vector magnitude so its result is

        ∑ F = Fₐ + F_b

indicate that the charge at y is negative, we analyze the direction of the force created by each charge

Charge A

as the electric field is incoming the charge is negative and as the test charge is negative both repel each other, consequently the force points to the right

Charge B

in this case the electric field lines are salient, therefore the charge is positive, consequently the force on the charge at y is attractive and points to the right

the sum of the two forces as both point to the right is a force that points to the right, that is, in the direction of the charge located at B