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
Alisiya [41]
2 years ago
11

It has been argued that power plants should make use of off-peak hours to generate mechanical energy and store it until it is ne

eded during peak load times. One suggestion has been to store the energy in large flywheels spinning on nearly frictionless ball bearings. Consider a flywheel made of iron (density 7800 kg/m3 ) in the shape of a 10.0 cm thick uniform disk.
(a) What would the diameter of such a disk need to be if it is to store 10.0 megajoules of kinetic energy when spinning at 90.0 rpm about an axis perpendicular to the disk at its center?

(b) What would be the centripetal acceleration of a point on its rim when spinning at this rate?
Physics
1 answer:
sdas [7]2 years ago
3 0

Answer:

Explanation:

90 rpm = 90 / 60 rps

= 1.5 rps

= 1.5 x 2π rad /s

angular velocity of flywheel

ω = 3π rad /s

Let I be the moment of inertia of flywheel

kinetic energy = (1/2) I ω²

(1/2) I ω² = 10⁷ J

I = 2 x  10⁷ / ω²

=2 x  10⁷ / (3π)²

= 2.2538 x 10⁵ kg m²

Let radius of wheel be R

I = 1/2 M R² , M is mass of flywheel

= 1/2 πR² x t x d x R² , t is thickness , d is density of wheel .

1/2 πR⁴ x t x d = 2.2538 x 10⁵

R⁴ = 2 x 2.2538 x 10⁵ / πt d

= 4.5076 x 10⁵ / 3.14 x .1 x 7800

= 184

R= 3.683 m .

diameter = 7.366 m .

b ) centripetal accn required

= ω² R

= 9π² x 3.683

= 326.816 m /s²

You might be interested in
What are two ways to increase impulse?
Pepsi [2]

Answer:

increase the time the force acts or you could increase the number of temptations.

hope this helped!

5 0
3 years ago
Two waves overlap producing a new wave that exhibits destructive
suter [353]

Answer:B

Explanation:

8 0
3 years ago
Read 2 more answers
For sprinters running at 12 m/s around a curved track of radius 26 m, how much greater (as a percentage) is the average total fo
Snezhnost [94]

Answer:

114.86%

Explanation:

In both cases, there is a vertical force equal to the sprinter's weight:

Fy = mg

When running in a circle, there is an additional centripetal force:

Fx = mv²/r

The net force is found with Pythagorean theorem:

F² = Fx² + Fy²

F² = (mv²/r)² + (mg)²

F² = m² ((v²/r)² + g²)

F = m √((v²/r)² + g²)

Compared to just the vertical force:

F / Fy

m √((v²/r)² + g²) / mg

√((v²/r)² + g²) / g

Given v = 12 m/s, r = 26 m, and g = 9.8 m/s²:

√((12²/26)² + 9.8²) / 9.8

1.1486

The force is about 114.86% greater (round as needed).

5 0
2 years ago
pulse train with a frequency of 1 MHz is counted using a modulo-1024 ripple-counter built with J-K flip flops. For proper operat
omeli [17]

Answer:

The maximum permissible propagation delay per flip flop stage is<u> 100 </u>n sec

Explanation:

1024 ripple counter has 10 J-K flip flops(210 = 1024).  

So the total delay will be 10×x where x is the delay of each J-K flip flops.

The period of the clock pulse is 1× 10⁻⁶ s.

Now

10x <= 10⁻⁶ s

x <= 100 ns

x= 100 ns for prpoer operation.

pulse train with a frequency of 1 MHz is counted using a modulo-1024 ripple-counter built with J-K flip flops. For proper operation of the counter, the maximum permissible propagation delay per flip flop stage is <u>100 </u>n sec.

4 0
3 years ago
Scuba divers are warned that if they must make a rapid ascent, they should exhale on the way up. If a diver rapidly ascends to t
Whitepunk [10]

Air for a diver comes out of a high pressure tank at - Same- pressure compared to the water around the diver (metered by the regulator).

This means the lungs are inflated with - Highly pressurized- gas.

This does not adversely affect the diver when deep underwater, because the entire environment around the diver is at -Same - pressure.

If the diver suddenly surface, the air in the alveoli in the lungs will still be at - a higher - pressure compared to the air around the diver, which will be at - a lower - pressure.

The gas in the diver's lungs will - expand - and can damage the alveoli.

5 0
3 years ago
Other questions:
  • I need a sentence for the word sandy soil
    15·2 answers
  • A beam of light has a wavelength of 4.5 x10^-7 meter in a vacuum. the frequency of this light is
    13·1 answer
  • how do you relate the equations for kinetic and potential energy to illustrate the law of conservation of energy?
    9·1 answer
  • A rigid tank initially contains 3kg of carbon dioxide (CO2) at a pressure of 3bar.The tank is connected by a valve to a friction
    12·1 answer
  • Work is being done in which of these situations? All motions are at a constant velocity (including velocity = zero).
    5·2 answers
  • Which example best demonstrates how unbalanced forces change the speed of an object's motion? A) A child on a bicycle braking at
    15·2 answers
  • If a rocket-powered sled is accelerated to a speed of 440 m/s in 2.20 seconds, then what is the acceleration?
    14·1 answer
  • At what temperature did the substance in the test tube into a solid?
    5·1 answer
  • Find the acceleration produced.
    6·2 answers
  • A large truck is moving at 22.0 m/s. if its momentum is 125,000 kg • meters per second, what is the truck's mass? 176 kg 2750 kg
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!