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2 years ago

A crane moves a 250 kg scoreboard from the ground to the height of 100 m. What is the work done on the scoreboard?

Physics

2 answers:

Mazyrski [523]2 years ago

7 0

If you’re doing potential and kinetic energy then the answer is potential.

Sveta_85 [38]2 years ago

5 0

Answer:

You will have to do the last PE - the initial PE

Explanation:

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Explain how skeletal muscles work in pairs. plzzzz answer asap !!

Olegator [25]

Answer:

it holds the bone and helps to move

I don't know if this is right

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2 years ago

Melanye and Kaitlynn were traveling on a train for 6 hours. Over that time the train was at an average velocity of 70km/hr west.

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The way he got the wrong guy to get back into the car he was just saying that I didn’t need it for me so he said no I’m gonna do tell you I have a little girl that was going on a little bit of a girl and I

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2 years ago

The histogram below shows the number of downloads of a song over time.

Allisa [31]

Given data:

It is a graphical display where the data is grouped in to ranges

A diagram consists rectangles, whose area is proportional to frequency of a variable and whose width is equal to the class interval.

It is an accurate representation of the distribution of numerical data.

From Figure:

Each box in the graph (small rectangle box) is assumed to be one download. So, in the graph the time between 8 p.m to 9 p.m, the number of downloads are 8.75 approximately (because the last box is incomplete, therefore 8 complete boxes and 9th is more than half).

So, We conclude that the total number of downloads are approximately 9 in the time span of 8 p.m. to 9 p.m.

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2 years ago

Which of the following statements describes an interaction between the geosphere and atmosphere?

german

B is the answer, I’m really good at this subject

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2 years ago

Read 2 more answers

A mass of 1 slug, when attached to a spring, stretches it 2 feet and then comes to rest in the equilibrium position. Starting at

Vesna [10]

Answer:

$Y=(\dfrac{3}{16}+t \dfrac{3}{8})e^{-2t}-\dfrac{3}{16}cos 4t$

Explanation:

Given that m= 1 slug and given that spring stretches by 2 feet so we can find the spring constant K

mg=k x

1 x 32= k x 2

K=16

And also give that damping force is 8 times the velocity so damping constant C=8.

We know that equation for spring mass system

my''+Cy'+Ky=F

Now by putting the values

1 y"+8 y'+ 16y=6 cos 4 t ----(1)

The general solution of equation Y=CF+IP

Lets assume that at steady state the equation of y will be

y(IP)=A cos 4t+ B sin 4t

To find the constant A and B we have to compare this equation with equation 1.

Now find y' and y" (by differentiate with respect to t)

y'= -4A sin 4t+4B cos 4t

y"=-16A cos 4t-16B sin 4t

Now put the values of y" , y' and y in equation 1

1 (-16A cos 4t-16B sin 4t)+8( -4A sin 4t+4B cos 4t)+16(A cos 4t+ B sin 4t)=6sin4 t

So by comparing the coefficient both sides

-16A+32B+16A=0 So B=0

-16 B-32 A+16B=6 So A=-3/16

y=-3/16 cos 4t

Now to find the CF of differential equation 1

y"+8 y'+ 16y=6 cos 4 t

Homogeneous version of above equation

$m^2+8m+16=0$

So $CF =(C_1+tC_2)e^{-2t}$

So the general equation

$Y=(C_1+tC_2)e^{-2t}-3/16 cos 4t$

Given that t=0 Y=0 So

$C_1=\dfrac{3}{16}$

t=0 Y'=0 So

$C_2 =\dfrac{3}{8}$

$Y=(\dfrac{3}{16}+t \dfrac{3}{8})e^{-2t}-\dfrac{3}{16}cos 4t$

The above equation is the general equation for motion.

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2 years ago