Physics, 29.07.2019 23:20 jackbruski

Ahorizontal block-spring system with the block on a frictionless surface has total mechanical energy e = 50.9 j and a maximum displacement from equilibrium of 0.204 m. (a) what is the spring constant? n/m (b) what is the kinetic energy of the system at the equilibrium point? j (c) if the maximum speed of the block is 3.45 m/s, what is its mass? kg (d) what is the speed of the block when its displacement is 0.160 m? m/s (e) find the kinetic energy of the block at x = 0.160 m. j (f) find the potential energy stored in the spring when x = 0.160 m. j (g) suppose the same system is released from rest at x = 0.204 m on a rough surface so that it loses 12.2 j by the time it reaches its first turning point (after passing equilibrium at x = 0). what is its position at that instant? m

Answers: 3

Show answers

Answers

Answer from: dontcare95

(a) 2446 N/m

When the spring is at its maximum displacement, the elastic potential energy of the system is equal to the total mechanical energy:

$E=U=\frac{1}{2}kA^2$

where

U is the elastic potential energy

k is the spring constant

A is the maximum displacement (the amplitude)

Here we have

U = E = 50.9 J

A = 0.204 m

Substituting and solving the formula for k,

$k=\frac{2E}{A^2}=\frac{2(50.9)}{(0.204)^2}=2446 N/m$

(b) 50.9 J

The total mechanical energy of the system at any time during the motion is given by:

E = K + U

where

K is the kinetic energy

U is the elastic potential energy

We know that the total mechanical energy is constant: E = 50.9 J

We also know that at the equilibrium point, the elastic potential energy is zero:

$U=\frac{1}{2}kx^2=0$ because x (the displacement) is zero

Therefore the kinetic energy at the equilibrium point is simply equal to the total mechanical energy:

K=E=50.9 J

The maximum speed of the block is v = 3.45 m/s, and it occurs when the kinetic energy is maximum, so when

K = 50.9 J (at the equilibrium position)

Kinetic energy can be written as

$K=\frac{1}{2}mv^2$

where m is the mass

Solving the equation for m, we find the mass:

$m=\frac{2K}{v^2}=\frac{2(50.9)}{(3.45)^2}=8.55 kg$

(d) 2.14 m/s

When the displacement is

x = 0.160 m

The elastic potential energy is

$U=\frac{1}{2}kx^2=\frac{1}{2}(2446)(0.160)^2=31.3 J$

So the kinetic energy is

K=E-U=50.9 J-31.3 J=19.6 J

And so we can find the speed through the formula of the kinetic energy:

$K=\frac{1}{2}mv^2 \rightarrow v=\sqrt{\frac{2K}{m}}=\sqrt{\frac{2(19.6)}{8.55}}=2.14 m/s$

(e) 19.6 J

The elastic potential energy when the displacement is x = 0.160 m is given by

$U=\frac{1}{2}kx^2=\frac{1}{2}(2446)(0.160)^2=31.3 J$

And since the total mechanical energy E is constant:

E = 50.9 J

the kinetic energy of the block at this point is

K=E-U=50.9 J-31.3 J=19.6 J

(f) 31.3 J

The elastic potential energy stored in the spring at any time is

$U=\frac{1}{2}kx^2$

where

k = 2446 N/m is the spring constant

x is the displacement

Substituting

x = 0.160 m

we find the elastic potential energy:

$U=\frac{1}{2}kx^2=\frac{1}{2}(2446)(0.160)^2=31.3 J$

(g) x = 0

The postion at that instant is x = 0, since it is given that at that instant the system passes the equilibrium position, which is zero.

Answer from: Quest

Acetic acid /əˈsiːtɪk/, systematically named ethanoic acid /ˌɛθəˈnoʊɪk/, is a colourless liquid organic compound with the chemical formula ch3cooh (also written as ch3co2h or c2h4o2). when undiluted, it is sometimes called glacial acetic acid. vinegar is no less than 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water. acetic acid has a distinctive sour taste and pungent smell. in addition to household vinegar, it is mainly produced as a precursor to polyvinyl acetate and cellulose acetate. it is classified as a weak acid since it only partially dissociates in solution, but concentrated acetic acid is corrosive and can attack the skin.acetic acidnamespreferred iupac nameacetic acidsystematic iupac nameethanoic acidother namesvinegar (when dilute); hydrogen acetate; methanecarboxylic acid[1][2]identifierscas number64-19-7 3d model (jsmol)interactive image3dmetb00009 reference506007chebichebi: 15366 chemblchembl539 chemspider171 drugbankdb03166 echa infocard100.000.528ec number200-580-7e numbere260 (preservatives)gmelin reference1380iuphar/bps1058keggd00010 meshacetic+acidpubchem cid176rtecs numberaf1225000uniiq40q9n063p un number2789inchiinchi=1s/c2h4o2/c1-2(3)4/h1h3,(h,3,4) key: qtbsbxvteameqo-uhfffaoysa-n smilescc(o)=o

Answer from: Quest

battery with hi vtge high val resist in series

Another question on Physics

Physics, 21.06.2019 22:00

Why do electron microscopes have higher resolving power than light microscopes?

Answers: 1

Answer

Physics, 22.06.2019 16:30

The sound level near a noisy air conditioner is 70 db. if two such units operate side by side, the sound level near the, would bea. 70dbb. 73 dbc. 105 dbd 140 db

Answers: 3

Answer

Physics, 22.06.2019 18:30

If a star is moving toward earth, it is

Answers: 2

Answer

Physics, 22.06.2019 19:30

Which of these has some mechanical energy? a. an atom b. heat inside earth c. a book on a shelf d. the fire from a lit match

Answers: 1

Answer

You know the right answer?

Ahorizontal block-spring system with the block on a frictionless surface has total mechanical energy...