the free body diagram shown above is for a 5 kg box on a rough surface being pulled to the right at a constant speed by a string that is at an angle of 30° above the horizontal. the coefficient of kinetic friction between the box and the surface is 0.30. the tension in this string is most nearly:

The angle of elevation of the shell must be approximately 25.840° in order to have a reach of 20 kilometers.

The shell experiments a parabolic motion, which is a combination of horizontal uniform motion and vertical uniform accelerated motion. If initial height of the shell is the same that its final height, then the range of the shell ([tex]d[/tex]), in meters, is described by the following expression:

[tex]d = \frac{v^{2}}{g}\cdot \sin 2\theta[/tex] (1)

Where:

If we know that [tex]v = 500\,\frac{m}{s}[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]d = 20000\,m[/tex], then the angle of elevation is:

[tex]\sin 2\theta = \frac{d\cdot g}{v^{2}}[/tex]

[tex]\theta = \frac{1}{2}\cdot \sin^{-1} \frac{d\cdot g}{v^{2}}[/tex]

[tex]\theta = \frac{1}{2}\cdot \sin^{-1} \frac{(20000\,m)\cdot \left(9.807\,\frac{m}{s^{2}} \right)}{\left(500\,\frac{m}{s} \right)^{2}}[/tex]

[tex]\theta \approx 25.840^{\circ}[/tex]

The angle of elevation of the shell must be approximately 25.840° in order to have a reach of 20 kilometers.

To learn more on parabolic motion, we kindly invite to check this question: https://brainly.com/question/1259873

Explanation:

what exactly are you asking for?

Answer:

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

f is the force

m is the mass

From the question

f = 24 N

m = 6 kg

We have

[tex]a = \frac{24}{6} = 4 \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

-34.8n

Explanation:

when object in free fall, only force is the Force by weight,

which is 34.8 and direction is down.

If we use visible light to explore the sky, a greater part of the universe will not be visible.

During her PhD, Walker learnt that the universe is quite large. As a result, she would need a telescope to learn about the universe rather than a spaceship. Secondly, she learnt that it is impossible to explore the universe on a spaceship rather she had to depend on the principles of astronomy.

The visible spectrum comprises of electromagnetic waves of wavelength 400 nm - 700 nm. If we use visible light to explore the sky, a greater part of the universe will not be visible because we will be limited to seeing only the  visible light portion of the electromagnetic spectrum.

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

The power can be increased by decreasing the time it takes to load 10 items into the truck it can be done by using leverage and putting more boxes in the truck at the same time.

Power refers to the ability of doing work done per unit time, higher the power means more work has been done in less time. The SI unit of power is watt.

Work done is a physical quantity that refers to measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement.

Given:

10 people are loading 10 items in a truck

According to the question we have to maximize the power output.

To do this we need to increase work done per unit time. This can be done in a number of ways which include:

Using leverage and pulley techniques to increase the loading capacity of the individual, so that more work is done in less time and therefore increasing the power output of the work to be done.

The second method would be decreasing the time it takes to load the boxes into the truck which can be done if multiple boxes are loaded into the truck at the same time.

Therefore, the power can be increased by decreasing the time it takes to load 10 items into the truck it can be done by using leverage and putting more boxes in the truck at the same time.

Learn more about power here:

https://brainly.com/question/2289248

#SPJ9

Answer:

For example, when a car travels at a constant speed, the driving force from the engine is balanced by resistive forces such as air resistance and friction in the car's moving parts. The resultant force on the car is zero.

Explanation:

hope this helps

Answer:

zero

Explanation:

The acceleration of the car is zero, and and in this case the velocity is also zero. When your car is moving at constant velocity down a street, the net force must also be zero, according to Newton's First Law.

The energy conservation and trigonometry we can find the results for the questions about the movement of the acrobat are;

     a) The maximum speed is v = 4.89 m / s

     b) The maximum height is h = 1.22 m

The energy conservation is one of the most fundamental principles of physics, stable that if there are no friction forces the mechanistic energy remains constant. Mechanical energy is the sum of the kinetic energy plus the potential energies.

               Em = K + U

Let's write the energy in two points.

Starting point. Highest part of the oscillation

            Em₀ = U = m g h

Final point. Lower part of the movement

            [tex]Em_f[/tex] = K = ½ m v²

Energy is conserved.

            Emo = [tex]Em_f[/tex]  

            m g h = ½ m v²

            v² = 2 gh

Let's use trigonometry to find the height, see attached.

         h = L - L cos θ

         h = L (1- cos θ)

They indicate that the initial angle is tea = 48º and the length is L = 3.7 m, let's calculate.

         h = 3.7 (1- cos 48)

          h = 1.22 m

this  is the maximum height of the movement.

Let's calculate the velocity.  

          [tex]v= \sqrt{2 \ 9.8 \ 1.22}[/tex]  

          v = 4.89 m / s

In conclusion using the conservation of energy and trigonometry we can find the results for the questions about the movement of the acrobat are;

     a) The maximum speed is v = 4.89 m / s

     b) The maximum height is h = 1.22 m

Learn more here: brainly.com/question/13010190

Answer:

A covalent bond consists of the mutual sharing of one or more pairs of electrons between two atoms. These electrons are simultaneously attracted by the two atomic nuclei. A covalent bond forms when the difference between the electronegativities of two atoms is too small for an electron transfer to occur to form ions.

Explanation: hope it helps :)

Answer:

current forms when electromagnetic waves strike a semiconductor, removing some of its electrons.

Explanation:

Answer:

current forms when electromagnetic waves strike a semiconductor, removing some of its electrons.

trust me i just did it

Explanation:

A milliliter, abbreviated as ml or mL, is a unit of volume in the metric system. One milliliter is equal to one thousandth of a liter, or 1 cubic centimeter. In the imperial system, that's a small amount: . 004 of a cup

1. Since the body is thrown vertically upward, the only force acting on it as it rises and falls is gravity, which causes a constant downward acceleration with magnitude g = 9.8 m/s². Because this acceleration is constant, we can use the formula

v² - u² = 2a ∆x

where

u = initial speed

v = final speed

a = acceleration

∆x = displacement

At its maximum height, some distance y above the point where the body is launched, the body has zero velocity, so

0² - (20 m/s)² = 2 (-9.8 m/s²) y

Solve for y :

y = (20 m/s)² / (2 (9.8 m/s²)) ≈ 20.4 m

2. Relative to the ground, the body's maximum height is 60 m + 20.4 m ≈ 80.4 m.

3. At any time t ≥ 0, the body's vertical velocity is given by

v = 20 m/s - gt

At the highest point, we have

0 = 20 m/s - (9.8 m/s²) t

and solving for t gives

t = (20 m/s) / (9.8 m/s²) ≈ 2.04 s

4. The body's height y above the ground at any time t ≥ 0 is given by

y = 60 m + (20 m/s) t - 1/2 gt²

Solve for t when y = 0 :

0 = 60 m + (20 m/s) t - 1/2 (9.8 m/s²) t²

Using the quadratic formula,

t = (-b + √(b² - 4ac)) / (2a)

(and omitting the negative root, which gives a negative solution) where a = -1/2 (9.8 m/s²), b = 20 m/s, and c = 60 m. You should end up with

t ≈ 6.09 s

5. At the time found in (4), the body's velocity is

v = 20 m/s - g (6.09 s) ≈ -39.7 m/s

Speed is the magnitude of velocity, so the speed in question is 39.7 m/s.

Answer: 225N to the right

Explanation:

The pedaling force is to the right and of 325N.

The air resistance is to the opposite side (in this case to the left) of 100N.

To find Net force of an object with two opposite forces acting on them then we have to subtract the smaller force from the bigger force and but the direction of the bigger force, so

325N-100N=225N

The greater force is towards the right proving the direction of the Net force is to the right.

Therefore the Net force is 225N to the right.

Please mark me brainliest.

Answer:

c

Explanation:

The changing of color of a substance is not necessarily an indicator of a chemical change. For example, changing the color of a metal does not change its physical properties. However, in a chemical reaction, a color change is usually an indicator that a reaction is occurring.

The key phrase which describes zero (0) initial velocity is from rest.

When the velocity of an object at initial time is zero (0), it implies that the change in the displacement of the object with time is zero

[tex]v= \frac{\Delta x}{\Delta t} \\\\v_0 = 0[/tex]

Generally, when an starts its motion from rest, the initial velocity of the object will be zero. As the object acquires more momentum, the velocity increases with time.

Thus, we can conclude that the key phrase which describes zero (0) initial velocity is from rest.

Learn more about initial velocity here:https://brainly.com/question/19365526

Answer:

up swelling moves water horizontally

I only know the formula which is ω = 2πf

Explanation:

The speedometer of a motor car showed the following speeds in km per hour at the ends of successive intervals of 3 secs. 38.9, 52.8, 64.4. 73.6, 80.9, 86.1, 90.0, 92.5 Plot the velocity – time graph in convenient units and find from the graph, (a) The distance covered while the speed increased from 80

Answer:

Explanation:

The mass of the object can be found by using the formula

[tex]m = \frac{f}{a} \\ [/tex]

f is the force

a is the acceleration

From the question we have

[tex]m = \frac{42}{1.8} = 23.3333... \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

[tex]\boxed {\boxed {\sf C. \ 23.33 \ kg}}[/tex]

Explanation:

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

[tex]F=ma[/tex]

The mass of the ball is unknown. The ball is accelerating at 1.8 meters per second squared. An unbalanced force of 42 Newtons is applied to the ball.

Convert the units of force. 1 Newton is equal to 1 kilogram meter per second squared, so our answer of 42 Newtons is equal to 42 kg*m/s².

Substitute the values into the formula.

[tex]42 \ kg*m/s^1 = m * 1.8 \ m/s^2[/tex]

We are solving for the mass, so we must isolate the variable m. It is being multiplied by 1.8 meters per second squared. The inverse operation of multiplication is division. Divide both sides by 1.8 m/s².

[tex]\frac {42 \ kg*m/s^2}{1.8 \ m/s^2} = \frac{a*1.8 \ m/s^2}{1.8 \ m/s^2}[/tex]

[tex]\frac {42 \ kg*m/s^2}{1.8 \ m/s^2} =m[/tex]

The units of meters per second squared cancel.

[tex]\frac {42 \ kg}{1.8 } =m[/tex]

[tex]23.3333333 \ kg=m[/tex]

Round to the hundredth place. The 3 in the thousandth place tells us to leave the 3 in the hundredth place.

[tex]23.33 \ kg \approx m[/tex]

The mass of the ball is approximately 23.33 kilograms.

Answer:

Divide the number of times an event occurs by the duration of time to calculate frequency. For instance, Anna divides the number of webpage clicks (236) by the time spent on the site (one hour, or 60 minutes). She discovers that she gets 3.9 clicks every minute.

Explanation:

does this help?

Answer:

the suns pull

Explanation:

The Sun's pull on Earth is twice as large as Earth's pull on the much larger Sun.

Levelized production cost is a big challenge in the production of wind energy.

The main challenge in the production of wind energy is the high production cost. It has to minimize the Levelized Production Cost (LPC) which is the ratio between energy production cost and economic lifetime. This problem can be solved by doing modification in the structure of the turbine as well as we must ensure minimal energy loss.

The modification in the structure can produce more electrical energy and reduce the energy loss also provides more profit to the company so we can conclude that levelized production cost is a big challenge in the production of wind energy.

Learn more: https://brainly.com/question/25543609

Answer:

The answer is #3: The kinetic energy of water is converted by a generator into electric energy.

Explanation:

Hydropower plants capture the energy of falling water to generate electricity. A turbine converts the kinetic energy of falling water into mechanical energy. Then a generator converts the mechanical energy from the turbine into electrical energy.

Answer:

1) 4 x 25m = 100m

2) 0 because after 4 lengths, he's back at the starting block.

3) speed is distance over time so speed here is 100m/125s = 0.8m/s

4) ...

5) 100m / 1.25m/s = 80s

6.a) 100m / 0.5m/s = 200s

7.b) ... can't draw this now..

Answer:

All objects are composed of these atoms. ... Charged objects have an imbalance of charge - either more negative electrons than positive protons or vice versa. And neutral objects have a balance of charge - equal numbers of protons and electrons.

Explanation:

From Snell's law,  the angle of refraction is 38 degree approximately and the index of refraction is 1.13

The given refractive index is 1.61

If light approaches the gem at an angle of 80.0°, that means the angle of incidence is 80.0°

To calculate the angle of refraction, we will use Snell's law which state that:

n = sin i / sin r

where n = refractive index

Substitute all the parameters into the formula

1.61 = sin 80 / sin r

make sin r the subject of formula

sin r = sin 80 / 1.61

sin r = 0.611

r = [tex]Sin^{-1}[/tex](0.611)

r = 37.7

r = 38 degree (Approximately)

We will use the same formula to calculate the index of refraction of a material if the angle of incidence is 60° and the angle of refraction is 50°. That is,

n = sin i / sin R

Where n = index of refraction

i = Incidence

R = refraction

Substitute all the parameters to the formula

n = sin 60 / sin 50

n = 0.866 / 0.766

n = 1.13

Learn more here: https://brainly.com/question/24321580

The amount of heat needed to raise the temperature of a 2kg object from 15°C to 25°C is 34000J.

HOW TO CALCULATE SPECIFIC HEAT CAPACITY:

Where;

Learn more about how to calculate heat absorbed at: https://brainly.com/question/11194034?referrer=searchResults

Answer:

55.84 look at periodic table

so 55.84*3= 167.52gFe