A mover pushes a 20 kg crate across a level floor with a force of 200 n, but
a the crate accelerates at a rate of only 7.5 m/ s2 because a friction force
opposes the crate's motion. what is the magnitude of this force of friction?
200 n
force of friction
a. 50 n
b. 15 n
c. 25 n
d. 100 n

Answer:

he density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ

Explanation:

Answer:

[tex]\text{Weight} = \text{Mass} \times \text{Gravitational acceleration}[/tex]

Explanation:

Answer:

1)10 m/s

2) 20 m/s

3) 2 s

4) 500 m

5)1000 km/h

Average speed = distance travelled / time.

( note: distance must be in (m) and time in sec, if not then you convert ).

1) average speed = 20/2 = 10mls.

2) average speed = 100/5 = 20 m/s.

3) since we aren't given (time) let's call it x

so we replace the unknown time with x..

average speed = 2/x = 1

then cross multiply

you get x (the unknown time) as 2s {seconds}.

(to check if it's correct just add the time we got back into the equation and see if you would get a erage speed as 1m/s).

4) do the same, replace distance as x or any letter you want )

average speed = x/ 10 = 50

cross multiply

you get x = 500m {meters}

5) (we need to convert km to meters and time to secs because that's what we are working with).

200km = 200,000 m { to convert to meters you multiply the given by 1000, 1km = 1000m).

for 2h, we know that:

60 seconds makes 1 minute

60 minutes makes an hour.

so we multiply 60 by 60 we get 3600mins then we multiply it by 2 to get 7200 secs

so now

Average speed = 200,000/7200 = 27.77 m/s.

Here you go..

hope this helps

Good luck and ace that test.

Answer: A material called moderator is used to slow down the neutrons released during nuclear fission. The source's neutrons have a high speed and energy. The neutrons' speed is slowed by heavy water or graphite moderators.

Explanation:

Answer:

here

Explanation:

Unlike-poles attract: When a north pole and south pole point together, the arrows point in the SAME direction so the field lines can join up and the magnets pull together (attract).

As the box begins to oscillate, it will have minimum velocity at maximum displacement and maximum velocity at minimum displacement.

The force applied to box will cause a displacement of the box from equilibrium position to maximum position which increases as the applied force increases.

Therefore, as the box begins to oscillate, it will have minimum velocity at maximum displacement and maximum velocity at minimum displacement.

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Answer:

We know that a solar electrical panel converts sunlight to electricity by means of solar cells and then, the electricity can be used as any electrical current.

I am not familiar with solar heating panels but assume that a liquid is heated by sunlight and then circulated thru the area that needs heating - it converts heat from sunlight to usable heat. The heat energy could also be stored and delivered at a different time (accumulated during the day and delivered at night). This is somewhat similar to a company freezing water at night when electricity is cheaper and then using the cooled water during the day for cooling.

Answer:

Number of Wire Turns in the Coil.

Explanation:

The greater the number of turns of wire in the coil, the greater the inductance. Fewer turns of wire in the coil results in lesser inductance. More coils of wires indicate a greater amount of magnetic field force for a given amount of coil current.

Answer:

Pressure of .2 m^3 of bricks:

Pb = ρ g H = 1.8 ρw * 9.80 m/s^2 * .20 m = 1800  * 9.8 * .2 = 3530 Pascals

ρb = 1.8 ρw = 1.8    since the density of bricks is 1.8 that of water

Pw = 1 * 9.8 * 1000 * .2 = 1960 Pascals

W = P * A   pressure * Area = Force

Pnet = 1570 Pascals - pressure due to bricks under water

F = 1570 N/m^2 * .2m^2 = 63 N     force on pile of bricks

∑F=m.a

18 - 6 = 40 x a

12 = 40a

a = 0.3 m/s²

#solid in liquid

#solid in gas

#solid in solid

#solid in liquid

#Liquid in a gas

Answer:

F = F2 - F1     where F is the net force upwards

F = 5 - (.5 * 9.8) = (5 - 4.9) N = .1 N

Since there is a net force in the upwards direction the rocket should experience an upwards acceleration.

The correct answer from each drop-down menu are in this case:

In a given mechanical system, in which forms of energy related to electromagnetic or thermal phenomena are not present, it can be said that the total energy of the system is purely mechanical. Thus, the Principle of Conservation of Energy implies the conservation of mechanical energy.

This, in turn, is the sum of the amounts of kinetic energy and various forms of potential energy (gravitational and elastic among them). Although mechanical energy is always constant, the amount of each of its components can change such that the total energy remains constant.

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The most appropriate safety precaution that the archaeologist should take to protect against the alpha particles without overheating by wear a pair of normal leather gloves. Option D is correct.

The act of producing radiation spontaneously is known as radioactivity. This is accomplished by an unstable atomic nucleus that want to give up some energy in order to move to a more stable form.

Radiation is being employed to assist humanity in medical, academia, and industry, as well as to generate power.

Radiation is also important in agriculture, archaeology, space exploration, law enforcement, geology a variety of other fields.

The most appropriate safety precaution that the archaeologist should take to protect against the alpha particles without overheating by wear a pair of normal leather gloves.

Hence, option D is correct.

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Answer:

See below ~

Explanation:

The answers are

Sun

precipitation

run off

evaporation

seapage

condensation

Answer:weight is a vector.

Explanation: It is measured in Newtons (N) and has direction

Answer:

total gravity of mass on earth. it can measured by Newton

Explanation:

I think it will help you. follow me ok .

The true statements about magnetic fields and forces will be A,D and E.

An iron piece,alloy, or other substance with its constituent atoms arranged in such a way that it shows magnetism qualities,

The function of the magnet is attracting other iron-containing objects or aligning itself in a magnetic field.

There are two poles of the magnet;

1. North Pole.

2. South Pole.

The same poles repel each other, while the opposite poles attract each other. In a sense, south-south and north-north repel. While the north-south and the south-north attract each other.

The correct statements are;

(A). The north pole attracts the south pole of a magnet.

(D)Forces caused by magnetic fields are weaker farther from the magnet.

(E)Magnetic forces can act on an object even if the object isn't touching the magnet.

Hence, the true statements about magnetic fields and forces will be A,D and E.

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Answer:

Hydrochloric acid and sodium hydroxide interact, resulting in salt and a release of heat. As we can see, the result of the interaction of two highly aggressive compounds is table salt and water – compounds that are ultimately harmless, even beneficial, to human beings.

Explanation:

Don't forget to mark me brainliest: )

thank you!!!!

Answer:

B. man with a beard

Explanation:

it is not a genetic mutation because it is completely natural and common unlike the other options.

Given that the object is moving due north at 32 m/s, this simply expresses the velocity of the object.

This is a quantity that has magnitude but no direction. Examples include energy, work, speed, distance etc

This is a quantity which have both magnitude and direction. Example include acceleration, velocity, moment, displacement etc

Velocity is the rate of change of displacement with time.

Velocity = displacement / time

Velocity can be written as 4 m/s due east

This the distance travelled per unit time.

Speed = distance / time

Speed can be written as 4 m/s

Considering the question given above, we were told that the object is moving due north. This simply talks about the velocity.

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Why can you get a shock if you touch a metal doorknob after walking across a wool carpet is because you have gained neutrons; the doorknob has fewer electrons. This is further explained below.

Electrons can be defined as a stable subatomic particles with a negative electrical charge that is found in all atoms and serves as the major carrier of electricity in solids.

In conclusion, You have an unbalanced charge, while the doorknob is neutral. you have gained neutrons; the doorknob has fewer electrons.

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Answer:

Nuclear physics are the study of protons, and neutrons at the center of an atom. This study shows the interactions between atoms, including what holds them together in a small space. Nuclear physics include fission, fusion, and decay.

Answer:

Heart rate monitor I think

Explanation:

you would know how intense the pedaling is by knowing your heart beat rate as of the pedaling is so intense your heart beat increases and if it was not so much your pedaling is not so intense.

This works also for any other sports .

~--Hope this helped--~

Answer: it’s Heart rate monitor

Explanation:

you use a heart rate monitor to check your intensity level by seeing how fast your heart goes

F = 1520N

explanation:

by newton third law of motion every action has equal and opposite reaction so truck exert on it so F = 1520N

that's my answer

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200J

Explanation:

Change in the internet energy = Heat aborsbed - work done

800 - 600

200 J

Answer:

D. 200J

Explanation:

KE = 1/2mv²

KE = 1/2 x 5 x (10²)

KE = 250 J

Answer:

286.7 m

Explanation:

So we are assuming the PE of the falcon is converted to KE

KE = PE

1/2 (.480)(75)^2 = .480 (9.81)(h )    solve for h = 286.7 m

Answer:

If the engine is making sound, then the passer (like you) will be dead

ANYWAYS

but if it was silent you can hear it softly because since speed of light (the car) is lower  than the speed of sound ( horn )

Explanation:

since the car is going in Miles per second if you convert it to Speed of sound that is what is equals to

c=√K^s / ρ