1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
kirza4 [7]
3 years ago
6

The angular speed of digital video discs (DVDs) varies with whether the inner or outer part of the disc is being read. (CDs func

tion in the same way.) Over a 133min playing time, the angular speed varies from 570rpm to 1600rpm .Assuming it to be constant, what is the angular acceleration (in/rads sec ) of such a DVD?
Physics
1 answer:
Kitty [74]3 years ago
8 0

Answer:

α = 0.0135 rad/s²

Explanation:

given,

t = 133 min = 133 x 60 = 7980 s

angular speed varies from 570 rpm to 1600 rpm

now,

570 rpm = 570 \times \dfrac{2\pi}{60}

              = 59.69 rad/s

1600 rpm =  = 570 \times \dfrac{2\pi}{60}

              = 167.6 rad/s

using equation of rotational motion

ωf = ωi + αt    

167.6 = 59.7 + α x 7980

α  x 7980 = 107.9

α = 0.0135 rad/s²

You might be interested in
Transparent
marusya05 [52]

Answer:

A..................

4 0
3 years ago
What measures air pressure.?
Alekssandra [29.7K]
That depends on what type of pressure you are attempting to measure, to measure Atmospheric pressure, you would use a Barometer. To measure things like tires, you could use a Tire Pressure Gauge. For Industrial processes and boilers, you would use a Manometer. For pressure vessels, you would use a Bordon Gauge.   <span />
8 0
3 years ago
Read 2 more answers
P-weight blocks D and E are connected by the rope which passes through pulley B and are supported by the isorectangular prism ar
creativ13 [48]

Answer:

21.8°

Explanation:

Let's call θ the angle between BC and the horizontal.

Draw a free body diagram for each block.

There are 4 forces acting on block D:

Weight force P pulling down,

Normal force N₁ pushing perpendicular to AB,

Friction force N₁μ pushing parallel up AB,

and tension force T pushing parallel up AB.

There are 4 forces acting on block E:

Weight force P pulling down,

Normal force N₂ pushing perpendicular to BC,

Friction force N₂μ pushing parallel to BC,

and tension force T pulling parallel to BC.

Sum of forces on D in the perpendicular direction:

∑F = ma

N₁ − P sin θ = 0

N₁ = P sin θ

Sum of forces on D in the parallel direction:

∑F = ma

T + N₁μ − P cos θ = 0

T = P cos θ − N₁μ

T = P cos θ − P sin θ μ

T = P (cos θ − sin θ μ)

Sum of forces on E in the perpendicular direction:

∑F = ma

N₂ − P cos θ = 0

N₂ = P cos θ

Sum of forces on E in the parallel direction:

∑F = ma

N₂μ + P sin θ − T = 0

T = N₂μ + P sin θ

T = P cos θ μ + P sin θ

T = P (cos θ μ + sin θ)

Set equal:

P (cos θ − sin θ μ) = P (cos θ μ + sin θ)

cos θ − sin θ μ = cos θ μ + sin θ

1 − tan θ μ = μ + tan θ

1 − μ = tan θ μ + tan θ

1 − μ = tan θ (μ + 1)

tan θ = (1 − μ) / (1 + μ)

Plug in values:

tan θ = (1 − 0.4) / (1 + 0.4)

θ = 23.2°

∠BCA = 45°, so the angle of AC relative to the horizontal is 45° − 23.2° = 21.8°.

3 0
3 years ago
A 5.0-kg block of wood is placed on a 2.0-kg aluminum frying pan. How much heat is required to raise the temperature of both the
Shalnov [3]

Heat required to raise the temperature of a given system is

Q = ms\Delta T

here we know that

m = mass

s = specific heat capacity

\Delta T = change in temperature

now as we know that

mass of wood = 5 kg

mass of aluminium pan = 2 kg

change in temperature = 45 - 20 = 25 degree C

specific heat capacity of wood = 1700 J/kg C

specific heat capacity of aluminium = 900 J/kg C

now here we will find the total heat to raise the temperature of both

Q = m_1s_1\Delta T_1 + m_2s_2\Delta T_2

Q = 5 * 1700 * 25 + 2 * 900 * 25

Q = 212500 + 45000

Q = 257500 J

So heat required to raise the temperature of the system is 257500 J

4 0
3 years ago
A cart rolling at ground level has K = 1500 J. It comes to a ramp, rolls up the ramp to an elevated platform. When it's on this
Black_prince [1.1K]
The potential energy Wood be 1000
8 0
3 years ago
Other questions:
  • If we have less power, we most likely have (2 points)
    14·1 answer
  • How does a nuclear power plant produce electricity
    10·1 answer
  • Your pencil is 11 cm long . How long is it in millimeters?
    7·1 answer
  • Has scientific knowledge changed over time?
    8·1 answer
  • 1. why does the sun have the greatest amount of gravity in our solar system?
    11·2 answers
  • If the wavelength of a beam of light is decreased what happens to the momentum of the photons
    12·1 answer
  • How can the potential energy in magnets be used to create kinetic energy in an object without making contact?
    8·1 answer
  • Between the ball and the player's head, there are forces. Which of Newton's laws does this represent? Support your choice.
    12·2 answers
  • If you were to mix 10 grams of salt into 100 grams of water, how much will the total mass of the solution be?
    10·1 answer
  • Which of the following describes an electric current?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!