A 55 kg roller skater is at rest on a flat skating rink, a 198 N horizontal force is needed to set the skater in motion.
However, after the skater is in motion a horizontal force of 175 N is necessary to overcome the friction of 52N to keep
the skater moving at a constant velocity. Find the coefficient of kinetic friction.

Answer:

that is the awnser key if that is your work sheet

Explanation:

i hope it is right

The simple activities like walking, jumping, throwing, etc. involves kinetic energy. The kinetic energy of an asteroid falling towards earth is very large. The new kinetic energy when the mass doubles is 0.8 J.

The measure of the work an object can do by virtue of its motion is defined as the kinetic energy. When an object moves with a new constant speed after we perform a work, the energy which is transferred is the kinetic energy.

The kinetic energy is a scalar quantity and it depends on the mass and velocity of the object. Its SI unit is Joule.

The equation of kinetic energy is:

Kinetic energy = 1/2 m × v²

When m = 2m, then kinetic energy is:

Kinetic energy = 1/2 × 2m × v²

So when we double mass, Kinetic energy also doubles.

K.E = 0.8 J

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Answer:

What is the question? Yes thats true but what do you need help with?

Explanation:

Answer:

Acceleration

The Newton's law that explains the reason for the pain experienced by Stephanie when she spikes the ball is Newton's third law of motion.

Newton's third law of motion, states that, action and reaction are equal and opposite.

The force exerted on the ball when Stephanie spikes is equal to the reaction the ball exerts back on Stephanie. As the force Stephanie applied increases, the reaction she receive from the ball increases as well and the more pain she will feel.

Thus, we can conclude that, the Newton's law that explains the reason for the pain experienced by Stephanie when she spikes the ball is Newton's third law of motion.

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Answer:

One benefit I listed: a higher salary

Explanation:

He expands his career possibilities which can lead to a higher salary, better or more preferable hours, more vacation time, and numerous other potential outcomes.

Answer:

there is less mass to move so the 2kg ball will move faster. the kinetic energy of the 5kg ball will move slower due to the fact that it needs more energy to move if it has more mass.

Answer:

the 2kg ball

Explanation:

there is less mass to move so the 2kg ball will move faster. the kinetic energy of the 5kg ball will move slower due to the fact that it needs more energy to move if it has more mass.

Answer:

middle blocker

Explanation:

Answer:

B / 2 ) Middle blocker / hitter

Explanation:

took the test

Answer:

Measurement is important so we could measure certain things right. By taking measurements we can have a knowledge of sizes, lengths, widths etc.

Explanation:

trueee...................

Answer:

true

Explanation:

light is a form of energy which is radiation so true:)

Answer:

Calculating the question of whether or not to take it serious

D

Explanation:

Mutiply and alagrab to subterc

Answer:

All forces are either balanced or unbalanced and each force acts in different ways.

Answer:

B. 2m/s² south

Explanation:

Given parameters:

Net force  = 40N

Mass  = 20kg

Unknown:

Acceleration of the object = ?

Solution:

To solve this problem, we use;

            F = ma

F is the net force

m is the mass

a is the acceleration

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

          a = [tex]\frac{40}{20}[/tex]   = 2m/s²

The acceleration of the object is 2m/s² south

Answer:

b

Explanation:

Answer:

D

Explanation:

Water has a high surface tension because the water molecules on the surface are pulled together by strong hydrogen bonds. That means a drop of water will "want" to have the smallest possible surface area.

When a sound wave travels from copper into the lead, it will slow down. The correct option is A.

A sound wave is a type of mechanical wave that is created by vibrations and travels through a medium such as air or water. It is characterized by its frequency, wavelength, amplitude, and speed. Sound waves are responsible for the sensation of hearing in humans and other animals.

When a sound wave travels from one medium to another, the speed and direction of the wave may change, depending on the properties of the two media. The change in speed is determined by the density and elasticity of the two media.

In the given table, we can see that the speed of sound is higher in copper (5,010 m/s) than in lead (1,960 m/s).

The wave changing in frequency or getting completely absorbed are not accurate predictions for what will happen when a sound wave travels from copper into the lead because the frequency of a sound wave is determined by the source of the wave, and is not affected by the medium through which it travels. Additionally, sound waves are generally not completely absorbed when they encounter a new medium, but rather they undergo reflection, transmission, or a combination of both.

The wave speeding up is also not a correct prediction because lead has a lower speed of sound than copper. When a sound wave travels from a medium with a higher speed of sound to a medium with a lower speed of sound, the wave will slow down.

Therefore, The answer is A. The wave will slow down.

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Answer:A the wave will slow down

Explanation:

Answer:

1. 75 speed, 2. 90 second = 1hr. 30 second. 3. 125 = 1hr 60 seconds 4.

Answer:

Increase in strength of hurricanes

Explanation:

A possible result of rising ocean temperatures caused by global warming is an increase in the strength of hurricanes, which is the second option. As the ocean temperatures increase, more energy is available to fuel hurricanes, making them stronger and potentially more destructive.

Global warming is causing the earth's climate to change, which is having a significant impact on the world's oceans. As the temperature of the oceans increases, a variety of effects can occur. One of the most well-documented impacts is the increase in the strength of hurricanes. Hurricanes form over warm ocean waters, and as the water temperature rises, it provides more energy to the storm, making it more powerful. 

Hence, a possible result of rising ocean temperatures caused by global warming is an increase in the strength of hurricanes, which is the second option.

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Answer:

Choice C

m = F/a

Explanation:

[Force] F = [mass × acceleration] ma

× A) m = a/F → F ≠ a/m

× B) m = Fa → F ≠ m/a

✓ C) m = F/a → F = ma

× D) m = Fa/2 → F ≠ 2m/a

Answer:

ithink ....... sorry if it wrong

d

Answer:

88N

Explanation:

If the force of gravity acting on the box is 88N, then the normal force on the box is also 88N;

 The force of gravity is the vertical pull of gravity on a body.

The normal force is equal to the gravitational force pull on a body.

So the solution is 88N

Answer:

90J

Explanation:

as known that W=f×s

therefore 15×6

=90j

Answer:

B

Explanation:

what could i say except ur welcome

Answer:

id be scared because this thing is moving by its self at an alarming rate

Explanation:

Answer:

W=25.088J

Explanation:

W=Fx

W=mgx

W=3.2kg*9.8m/s^2*0.8m

W=25.088J

Answer:

The president is permitted to veto specific legislative acts, but Congress has ... and judicial appointments and on the approval for ratification of treaties. ... State shall have the Qualifications requisite for Electors of the most numerous Branch of the State Legislature. ... No Bill of Attainder or ex post facto Law shall be passed.

Explanation:

Answer:

After 11.9 seconds, the velocity will increase by approximately 2.7 m/s

Explanation:

Ignoring friction, we can simply say that the speed will increase by

11.9s × 473.3N / 2068.3kg

Which can be expressed as:

11.9s × 473.3kg·m/s² ÷ 2068kg

= (11.9 × 473.3 ÷ 2048.3) (kg·m/s² × s ÷ kg)

≈ 2.7 m/s

Answer:

Well this is tough. I'm not sure but you are smart and can push through it. YOU DONT need the someone telling you the answer when it is inside you.

hope this helps p

Answer:

a) If the mass is doubled, then the period is increased by [tex]\sqrt{2}[/tex]. Hence, the period of the system is 2.828 seconds.

b) If the mass is halved, then the period is reduced by [tex]\frac{\sqrt{2}}{2}[/tex]. Hence, the period of the system is 1.414 seconds.

c) The period of the system does not depend on amplitude. Hence, the period of the system is 2 seconds.

d) If the spring constant is doubled, then the period is reduced by [tex]\frac{\sqrt{2}}{2}[/tex]. Hence, the period of the system is 1.414 seconds.

Explanation:

The statement is incomplete. We proceed to present the complete statement: A block attached to a spring with unknown spring constant oscillates with a period of 2.00 s. What is the period if a. The mass is doubled? b. The mass is halved? c. The amplitude is doubled? d. The spring constant is doubled?

We have a block-spring system, whose angular frequency ([tex]\omega[/tex]) is defined by the following formula:

[tex]\omega = \sqrt{\frac{k}{m} }[/tex] (1)

Where:

[tex]k[/tex] - Spring constant, measured in newtons per meter.

[tex]m[/tex] - Mass, measured in kilograms.

And the period ([tex]T[/tex]), measured in seconds, is determined by the following expression:

[tex]T = \frac{2\pi}{\omega}[/tex] (2)

By applying (1) in (2), we get the following formula:

[tex]T = 2\pi\cdot \sqrt{\frac{m}{k} }[/tex]

a) If the mass is doubled, then the period is increased by [tex]\sqrt{2}[/tex]. Hence, the period of the system is 2.828 seconds.

b) If the mass is halved, then the period is reduced by [tex]\frac{\sqrt{2}}{2}[/tex]. Hence, the period of the system is 1.414 seconds.

c) The period of the system does not depend on amplitude. Hence, the period of the system is 2 seconds.

d) If the spring constant is doubled, then the period is reduced by [tex]\frac{\sqrt{2}}{2}[/tex]. Hence, the period of the system is 1.414 seconds.