Trying to help my brother but i dont remember question 8. Pls help, thank you

Answer:

ITS D !!!

Explanation:

IN ME WE TRUST

When you sit on the chair, your body will exert a downward force and in reaction, the chair pushes up on your body. Hence, option D is correct.

A building experiences a reaction force when it rests against another object. Calculating the reaction forces at the supports as a result of the forces operating on the beam is a necessary step in the analysis of a beam structure. The reaction forces can be calculated using a free body diagram of the entire beam.

Corrosion can be caused by reaction forces. For instance, due to the system's increased stiffness, reaction forces increase when bearing clearances are reduced from 350 mm to 150 mm.

According to the question, when the body will exert a downward force that is mg due to gravity, the chair will make a normal reaction force which will be equal to the force applied by the body on the chair.

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Answer:

Problem 1-

The acceleration = 5 m/s²

Problem 2 -

The acceleration = 3.[tex]\overline 3[/tex] m/s²

Problem 3 -

The acceleration = 2.5 m/s²

Problem 4-

The force applied = 7.5 N

Problem 5-

The mass of the object,  = 0.5 kg.

Explanation:

Problem 1-

The mass of the ball, m = 0.5 kg

The force (applied) with which it was hit, F = 2.5 N

The acceleration, a = Force/Mass = 2.5 N/(0.5 kg) = 5 m/s²

The acceleration = 5 m/s²

Problem 2 -

The mass of the box, m = 15 kg

The force (applied) with which it was hit, F = 50 N

The acceleration, a = Force/Mass = 50 N/(15 kg) = 10/3 = 3.[tex]\overline 3[/tex] m/s²

The acceleration = 3.[tex]\overline 3[/tex] m/s²

Problem 3 -

The mass of the object, m = 2.0 kg

The force (applied) with which it was hit, F = 5.0 N

The acceleration, a = Force/Mass = 5.0 N/(2.0 kg) = 2.5 m/s²

The acceleration = 2.5 m/s²

Problem 4-

The mass of the object, m = 3.0 kg

The acceleration, a, of the object = 2.5 m/s²

The force applied to it, F = Mass × Acceleration = 3.0 kg × 2.5 m/s² = 7.5 N

The force applied = 7.5 N

Problem 5-

The acceleration, a, of the object = 12 m/s²

The force applied, F = 6.0 N

The mass of the object, m = Force/Acceleration = 6.0 N/(12 m/s²) = 0.5 kg

The mass of the object,  = 0.5 kg.

Answer:

16: x4

17 x2

18; 4.5 for q1 and 4.5 for q2

Explanation:

Answer:

Explanation:

The work done by an object can be found by using the formula

From the question

weight = 2 N

distance = 4 m

We have

workdone = 2 × 4

We have the final answer as

Hope this helps you

Answer:

The average speed is 3.98 [tex]\frac{m}{s}[/tex]

Explanation:

Speed ​​is a scalar quantity that shows the relationship between the distance traveled and the time taken.

In other words, speed is a scalar quantity that determines the ratio of the distance traveled by a body or object and the time it takes to cover that distance. Speed ​​does not take direction into account.

Average speed refers to the total distance traveled during a given time, which is equivalent to saying that it is the ratio of distance and time.

[tex]average speed=\frac{total distance}{totaltime}[/tex]

In this case you know that a runner completes two laps around a 400 m track, so the total distance traveled is 800 m.

On the other hand, you know that the runner completes the first lap in 1 min 32 s, and the second lap in 1 min 49 s. Being 1 min equivalent to 60 s, the first round is completed in 92 s and the second round in 109 s. So the total time to complete the two laps around the track is 92 s + 109 s = 201 s.

That is, being:

and replacing in the definition of average speed:

[tex]average speed=\frac{800 m}{201 s}[/tex]

you get:

average speed= 3.98 [tex]\frac{m}{s}[/tex]

The average speed is 3.98 [tex]\frac{m}{s}[/tex]

Answer:

3.98 m/s

Explanation:

To find speed, use the formula:

Speed = Distance / time

The Distance is 400 + 400 = 800 m

The time in seconds is (60 + 32) + (60 + 49) = 201 sec

Now use the formula

Speed = 800 m / 201 s = 3.98 m/s

Answer:

C)Gravitational force would decrease by a factor of 2.

Explanation:

Hope this helps :)

Answer:

Magnitude of frictional force = 30 N

Explanation:

According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:

Fn=m.a

The net force is the vector addition of each individual force. If the sum of all the forces acting on an object is zero, then the acceleration is zero. That means the object moves at a constant speed or is at rest.

When an object is pushed across a horizontal rough surface, there are two forces acting in the direction of the motion: The applied force and the frictional force.

If the applied force is greater than the frictional force, then the object moves at a constant positive acceleration. If the frictional force is greater than the applied force, then the object won't move at all (if it was at rest) or will start a deaccelerated motion (braking).

Finally, if both forces are equal, the object will move at a constant speed or remains at rest. Since the box is moving at a constant speed, we can conclude the frictional force equals the applied force:

Magnitude of frictional force = 30 N

The best image of galaxy is second option.

Galaxies are vast systems of gravity-bound gas, dust, dark matter, and anything from a million to a trillion stars. Supermassive black holes are expected to be present at the centers of almost all big galaxies. The sun is merely one of 100 to 400 billion rotating stars in our own galaxy, the Milky Way.

There are more galaxies visible as we gaze farther into space. According to a 2016 study, there are two trillion, or two million million, galaxies in the observable universe. While some of those far-off systems resemble our own Milky Way galaxy, others are very dissimilar,

There are three general types of galaxies elliptical, spiral, and irregular.

So the best shape is second option elliptical with boundary.

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Explanation:

Hey there!

We know that the objects in vacuum falls equally on the surface or bottom. As there is no air resistance in vacuum, the objects has equal stabdard acceleration. (i.e g = 9.8m/s^2)

So, the acceleration due to gravity is 9.8m/s^2.

Hope it helps....

Answer:

6.125kg    

Explanation:

Given parameters:

  Force  = 49N

  acceleration  = 8m/s²

Unknown:

Mass of the object  = ?

Solution:

From newton's second law;

    Force  = mass x acceleratioin

    49 = mass x 8

       mass  = [tex]\frac{49}{8}[/tex]   = 6.125kg    

Answer:

the heat is growing the particles bigger

Explanation:

Answer:

B

Explanation:

Answer:

answer is B

Explanation:

took the test

Krill and plankton are two groups of organisms found in the ocean. Krill are species of crustacean related to shrimp, and serve as a very important link in the food chain of the sea. Plankton consist of a larger group of organisms with much more variety, including bacteria, algae, protozoans, jellyfish and some species of cephalopods.

Propulsion

The primary factor that determines whether a species is plankton or not is propulsion. Plankton organisms lack the ability to swim against the tide, and instead float from place to place on sea currents. They may be capable of some movement, and some types of plankton can even hunt for food, but none is powerful enough to make its own headway through the ocean. Adult krill are capable of swimming against currents, but their larvae and eggs fall into the plankton category.

Variation

Krill are crustaceans of the Euphausiacea order, which consists of 86 different species. Plankton, on the other hand, can come from a wide variety of different species and orders. Plankton fall into three broad categories, depending on their primary function. Phytoplankton are plant-like organisms, capable of photosynthesis. Zooplankton are animal plankton species that get their nutrients by eating other microscopic organisms. Bacterioplankton are the smallest plankton, and often serve as food for zooplankton and other lifeforms.

Appearance

Krill species have similar characteristics and generally resemble tiny shrimp. Most species reach around 2 centimeters (0.8 inches) as adults, while the largest species can reach sizes of up to 15 centimeters (5.9 inches). Plankton, on the other hand, consists of organisms of many different shapes and sizes. The smallest categories include microscopic viruses, protozoans, small crustaceans, and other tiny organisms. At the larger end of the scale, megaplankton are any plankton over 2 centimeters (0.8 inches) in size, and include large animals, such as cephalopods and jellyfish. The largest plankton is the lion's mane jellyfish, which can reach 2.5 meters (8.2 feet) in diameter and grow tentacles more than 36.5 meters (120 feet) long.

Role

Plankton and krill serve similar, but slightly different, roles in the food chain. Phytoplankton synthesize nutrients, while bacterioplankton recycle nutrients from decomposing matter in the ocean, providing some of the fundamental sources of nutrition for all ocean creatures. Zooplankton serve to concentrate those nutrients by eating smaller plankton and serving as food for larger creatures. Krill are one step up in the food chain, eating plankton and serving as a nutrient bridge from microscopic life forms to larger fish and mammals.

Answer:

9) a = 25 [m/s^2], t = 4 [s]

10) a = 0.0875 [m/s^2], t = 34.3 [s]

11) t = 32 [s]

Explanation:

To solve this problem we must use kinematics equations. In this way we have:

9)

a)

[tex]v_{f}^{2} = v_{i}^{2}-(2*a*x)\\[/tex]

where:

Vf = final velocity = 0

Vi = initial velocity = 100 [m/s]

a = acceleration [m/s^2]

x = distance = 200 [m]

Note: the final speed is zero, as the car stops completely when it stops. The negative sign of the equation means that the car loses speed or slows down as it stops.

0 = (100)^2 - (2*a*200)

a = 25 [m/s^2]

b)

Now using the following equation:

[tex]v_{f} =v_{i} - (a*t)[/tex]

0 = 100 - (25*t)

t = 4 [s]

10)

a)

To solve this problem we must use kinematics equations. In this way we have:

[tex]v_{f} ^{2} = v_{i} ^{2} + 2*a*(x-x_{o})[/tex]

Note:  The positive sign of the equation means that the car increases his speed.

5^2 = 2^2 + 2*a*(125 - 5)

25 - 4 = 2*a* (120)

a = 0.0875 [m/s^2]

b)

Now using the following equation:

[tex]v_{f}= v_{i}+a*t\\[/tex]

5 = 2 + 0.0875*t

3 = 0.0875*t

t = 34.3 [s]

11)

To solve this problem we must use kinematics equations. In this way we have:

[tex]v_{f} ^{2} = v_{i} ^{2} + 2*a*(x-x_{o})[/tex]

10^2 = 2^2 + 2*a*(200 - 10)

100 - 4 = 2*a* (190)

a = 0.25 [m/s^2]

Now using the following equation:

[tex]v_{f}= v_{i}+a*t\\[/tex]

10 = 2 + 0.25*t

8 = 0.25*t

t = 32 [s]

Answer:

с

creates its own light, which is blocked by the Sun during an eclipse.

Explanation:

might not be right but its what i remember

Answer:

c.mass and the amount of matter

Answer:

A magnetic force can convert kinetic energy stored in a magnetic field to potential energy. Kinetic energy can convert potential energy stored in a gravitational field. A magnetic energy can convert potential energy stored in a gravitational field to kinetic energy.

Answer:

Hello

A. The muscle contracts causing the tendon to pull the bone.

Answer: A

Explanation: The muscle contracts causing the tendon to pull the bone.

Answer:

The different types of energy include thermal energy, radiant energy, chemical energy, nuclear energy, electrical energy, motion energy, sound energy, elastic energy and gravitational energy.

Answer:

Chemical energy

Explanation:

Ex. gasoline, chemical batteries, and wood

Answer:

hope this could help you

Answer:

Measurement is the assignment of a number to a characteristic of an object or event

Explanation:

Answer:

Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or event

Answer:

Explanation:

Hope this helps, cheers

Answer:

The covered distance was 1800 [m]

Explanation:

In order to solve this problem we must use the following formula of kinematics. It is important to make it clear that Branden's speed never changes during that time, or therefore the speed is constant.

[tex]x = x_{o}+v*t\\[/tex]

where:

x = distance [m]

Xo = initial position = 0

v = velocity = 6 [m/s]

t = 300 [s]

Now replacing we have:

x = 0 + (6*300)

x = 1800 [m]

Answer: also 13

Explanation: because there have to be an equal number of protons,neutrons,and electrons to make the atom stable.