Chiếu tia sáng lên một gương phẳng biết góc tới bằng 15⁰ hãy tính góc phản xạ bằng bao nhiêu

Answer:

Explanation:

They traveled this distance in 2 parts, essentially. Part 1 had an average speed for a certain number of hours, part 2 had an average speed for a certain number of hours, and those 2 parts taken together took them a distance of 364 km. In equation form, that looks like this:

km/hr part 1 + km/hr part 2 = 364 km

Now we need to find each part on the left side of that equation. Part 1 first:

We traveled 65 km/hr for 2 hours, so that took us

[tex]65\frac{km}{hr}*2hr[/tex] and canceling out the hour label, we have that in part 1 we got

65(2) = 130 km. Good. Now onto the second part, where our unknown is.

We traveled 78 km/hr the second part for x hours, so that took us

[tex]78\frac{km}{hr}*xhr[/tex] and canceling out the hour label, we have that in part 2 we got

78x km. Now we can fill in the main equation (the one in bold print)

130 km + 78x km = 364 km and subtracting 130 km from both sides:

78x km = 234 km and dividing by 78 km:

x = 3 hours. Part 2 took 3 hours. Part 1 took 2 hours, so the whole trip took 5 hours.

a. all systems work together to stabilize the body

Answer:A

Explanation:i just took the test

Answer:

2a.

a=1.13ms^-2

2b.

S=277m

2c.

V=27.7ms-¹

Explanation:

Initial Velocity (U)=22m/s¹

Final Velocity (V)=43m/s²

Time(t) =18.6s

a. a=V-U/t

a=43-22/18.6

a=1.129

a=1.13m/s²

2b.

S=ut+1/2 at²

s=22(10)+1/2×1.13(10)²

s= 220+0.57(10)²

s= 220+0.57(100)

s= 220+57

s=277m

2c.

V=U+AT

V=22+1.13(5)

V=22+5.65

V=22+5.7

V=27.7m/s¹

Answer:

Measurement is the act or the process of finding the size, quantity or degree of something.

Explanation:

We can measure the length, weight, and capacity (volume) of any given object.

Answer:

Q = 165.95 cm³ / s,  1)    v = [tex]\sqrt{0.55^2 + 19.6 y}[/tex],  2)  v = 2.05 m / s,

3)  d₂ = 1.014 cm

Explanation:

This is a fluid mechanics exercise

1) the continuity equation is

         Q = v A

where Q is the flow rate, A is area and v is the velocity

the area of ​​a circle is

        A = π r²

radius and diameter are related

        r = d / 2

substituting

       A = π d²/4

       Q = π/4   v d²

let's reduce the magnitudes

       v = 0.55 m / s = 55 cm / s

let's calculate

       Q = π/4   55   1.96²

       Q = 165.95 cm³ / s

If we focus on a water particle and apply the zimematics equations

        v² = v₀² + 2 g y

where the initial velocity is v₀ = 0.55 m / s

        v = [tex]\sqrt{0.55^2 + 2 \ 9.8\ y}[/tex]

        v = [tex]\sqrt{0.55^2 + 19.6 y}[/tex]

2) ask to calculate the velocity for y = 0.2 m

        v = [tex]\sqrt{0.55^2 + 19.6 \ 0.2}[/tex]

        v = 2.05 m / s

3) We write the continuous equation for this point 2

        Q = v₂ A₂

        A₂ = Q / v₂

let us reduce to the same units of the SI system

        Q = 165.95 cm³ s (1 m / 10² cm) ³ = 165.95 10⁻⁶ m³ / s

        A₂ = 165.95 10⁻⁶ / 2.05

        A₂ = 80,759 10⁻⁶ m²

area is

        A₂ = π/4   d₂²

        d₂ = [tex]\sqrt{4 A_2 / \pi }[/tex]

        d₂ = [tex]\sqrt{ \frac{4 \ 80.759 \ 10^{-6} }{\pi } }[/tex]

        d₂ = 10.14 10⁻³ m

        d₂ = 1.014 cm

Answer:

reducing the scale of the market for a new product

Explanation:

A product can be defined as any physical object or material that typically satisfy and meets the demands, needs or wants of customers. Some examples of a product are mobile phones, television, microphone, microwave oven, bread, pencil, freezer, beverages, soft drinks, automobiles, motorcycles, etc.

The use of technology in the manufacturing of a new product can be effectively and efficiently promoted in the market by doing the following;

I. Issuing a patent to a company that invents a new product. Patent can be defined as the exclusive or sole right granted to an inventor by a sovereign authority such as a government, which enables him or her to manufacture, use, or sell an invention for a specific period of time.

Generally, patents are used on innovation for products that are manufactured through the application of various technologies.

II. Paying a higher amount of money as wages for researchers who are saddled with the responsibility of making finding about a product.

III. Creating a training programs that would help to improve on the knowledge and skills of workers.

However, reducing the scale of the market for a new product in comparison with other products and standards does not help promote technological progress.

Answer:

A. Energy only is the answer to your question

Answer:

If you went to work your trap muscles you don't need a ton of fancy gym equipment. Here are four trapezius exercises you can perform using your own body.

Answer:

1.261 billion

Explanation:The distance between the earth and the moon in miles is 250,000,so in feet,The distance is 1.261 billion

Answer:

2000g

Explanation:

volume=mass/density

=2000/2.5

=800cm³

mass=density×volume

=800×2.5

=2000g

Explanation:

The answer is Electrons move between objects.

Answer:

Explanation:

1. Free fall implies an object falling under the gravitational influence only. During the flight, no other force acts on it except the gravitational pull.

2. Acceleration due to gravity is the earth's natural force of pull on all objects on its surface, close to its surface, or in the region where the force can be felt. This force pulls object to the surface of the earth.

3. Escape velocity is the required minimum velocity for an object to leave the gravitational influence of the earth. It has a constant value which can be determined by;

Escape velocity = [tex]\sqrt{2gR}[/tex]

where g is the gravitation force of the earth and R is the radius of the earth.

4. Centripetal force is the force of pull that is required to keep a rotation object in its curved path.

Answer:

(a) 37.5 kg

(b) 4

Explanation:

Force, F = 150 N

kinetic friction coefficient = 0.15

(a) acceleration, a = 2.53 m/s^2

According to the newton's second law

Net force = mass x acceleration

F - friction force = m a

150 - 0.15 x m g = m a

150 = m (2.53 + 0.15 x 9.8)

m = 37.5 kg

(b) As the block moves with the constant speed so the applied force becomes the friction force.

[tex]F = \mu m g \\\\150 = \mu\times 37.5\\\\\mu = 4[/tex]

Answer:

a is your answer.............

Answer:

It is respected as leaders are accountable to the people. The rule of law within a democratic country will dictate what actions is considered wrong and punishable to do in that country. This will prevent people from harming and violating each other to get what they want and form a stable and safe society

Answer:

True

Explanation:

When non-conservative forces are present, the amount of work done increases with the length of the path, this is true because, when a force is applied, the force does when and the non-conservative forces also do work. Since the non-conservative force work against the force  applied, this tend to increase the net work done by the applied force to compensate for the loss in energy due to the work done by the non-conservative forces.

Explanation:

Answer:

Electricity is the presence and flow of electric charge. Using electricity we can transfer energy in ways that allow us to do simple chores . it's best - known form is the flow of electrons through conductor such as copper wires. The world "electricity " is sometimes used to mean "electrical energy "

Explanation:

hope it is helpful to you ☆

[tex]kavya[/tex]

Answer:

Gravitational potential

Explanation:

Any object that is not on the surface of the Earth, but at a height instead has potential energy. Eventually, this can become kinetic energy once the object falls.

When an object is in a gravitational field, it has energy in its gravitational potential energy store.

Answer:

Explanation:

The equation for this is

F - f = ma

The thing that gets strange here is that, because the student is pulling his sister on the sled with the rope at an angle, some of his efforts are being wasted. The sled is only going to move forward (horizontally), so the vertical component of that force is useless. He's not actually pulling horizontally with that much force; we have to figure out how much using the following equation:

[tex]F=430cos35[/tex] to get that

F = 352 N

Everything else falls into place quite easily into the equation now:

352 - 180 = 41a and

172 = 41a so

a = 4.2 m/s/s

Answer:

The brightness of a light depends on the amplitude of the light wave, which is the extent the waves moves from their equilibrium position. The brightness is also related to the amount of light that is emitted or reflected by an object

Therefore, compared to dim light, light that look bright have a higher amplitude and emit or reflect more light energy (photons)

Explanation:

Answer:

a) i) x = 0.25 m, ii) x = 0.10 m, iii)  x = 0.050 m

b) i)  x = 0.40 m

Explanation:

a) For this exercise we use the rotational equilibrium equation, where we assume that the anticlockwise rotations are positive.

1) L = 2W  

we set our reference system in the center of the bar where the fulcrum is

              ∑τ = 0

              W 0.50 - L x = 0

              x = 0.50 W / L

we substitute the value

              x = 0.50 W / 2W

              x = 0.25 m

ii) L = 5W

we calculate

              x = 0.50 W / 5W

              x = 0.10 m

iii) L = 10 W

               x = 0.50 W / 10W

              x = 0.050 m

b) a new weight is placed at x₂ = 30 cm on the left side

              W 0.50 + W 0.30 - L x = 0

              x = (0.50 + 0.30) W / L

              x = 0.80 W / L

we calculate

i)  L = 2W

                x = 0.80 w / 2w

                x = 0.40 m

Answer:

the green ball has 4J more energy

Explanation:

The kinetic energy is given by the formula

K = 0.5 m v^2

the kinetic energy of the red ball:

K(red) = 0.5*10*3^2= 45J

of the green ball:

K(green)=0.5*8*3.5^2 = 49J

therefore the green ball has more energy by 4 Joules

Answer:

A.

Explanation:

The pad extends the time so the impulse changes.

Answer:

A. The pad extends the time so the impulse changes

Explanation:

in term of physics it has same mass:)