Which of the following means that an<br> image is real?

Modern wind turbines generate electricity from wind power. The large, massive blades have a large moment of inertia and carry a

ANTONII [103]

Answer:

Explanation:

a )

Each blade is in the form of rod with axis near one end of the rod

Moment of inertia of one blade

= 1/3 x m l²

where m is mass of the blade

l is length of each blade.

Total moment of moment of 3 blades

= 3 x $\frac{1}{3}$ x m l²

ml²

2 )

Given

m = 5500 kg

l = 45 m

Putting these values we get

moment of inertia of one blade

= 1/3 x 5500 x 45 x 45

= 37.125 x 10⁵ kg.m²

Moment of inertia of 3 blades

= 3 x 37.125 x 10⁵ kg.m²

= 111 .375 x 10⁵ kg.m²

c )

Angular momentum

= I x ω

I is moment of inertia of turbine

ω is angular velocity

ω = 2π f

f is frequency of rotation of blade

d )

I = 111 .375 x 10⁵ kg.m² ( Calculated )

f = 11 rpm ( revolution per minute )

= 11 / 60 revolution per second

ω = 2π f

= 2π x 11 / 60 rad / s

Angular momentum

= I x ω

111 .375 x 10⁵ kg.m² x 2π x 11 / 60 rad / s

= 128.23 x 10⁵ kgm² s⁻¹ .

4 0

3 years ago

8. A turtle crawls along a straight line, which we will call the x-axis with the positive direction to the right. The equation f

pychu [463]

(a) The turtle's initial velocity is 4 m/s, initial position of the turtle is 5 cm, and initial acceleration is -1.25 m/s².

(b) The time when the velocity of the turtle is zero is 3.2 s.

(c) The time taken for the turtle to return to its starting point is 6.4 s.

(d) The time taken for the turtle to travel 30 cm is 0.08 s.

<h3>Initial velocity of the turtle</h3>

The initial velocity of the turtle is calculated as follows;

$v = \frac{dx}{dt} \\\\x = 5 + 4t -0.625t^2\\\\v(t) = 4 - 1.25t\\\\v(0) = 4-0\\\\v(0) = 4 \ m/s$

<h3>Initial acceleration of the turtle</h3>

The initial acceleration of the turtle is calculated as follows;

$a = \frac{dv}{dt} \\\\v(t) = 4 - 1.25t\\\\a = -1.25\ m/s^2$

<h3>Initial position of the turtle</h3>

x(t) = 5 + 4t - 0.625t²

x(0) = 5 cm

<h3>Time when the velocity becomes zero</h3>

v(t) = 4 - 1.25t

0 = 4 - 1.25t

1.25t = 4

t = 4/1.25

t = 3.2 s

<h3>Time taken to return to starting point</h3>

The total distance traveled is calculated as follows

v² = u² + 2ad

0 = (4)² + 2(-1.25)d

0 = 16 - 2.5d

2.5d = 16

d = 16/2.5

d = 6.4 m

Time to travel the given distance;

d = ut + ¹/₂at²

6.4 = (4)t + ¹/₂(-1.25)t²

6.4 = 4t - 0.625t²

0.625t² - 4t + 6.4 = 0

solve the quadratic equation using formula method;

t = 3.2 s

The time travel the distance two times, = 2 x 3.2 s = 6.4 s

<h3>Time taken for the turtle to travel 30 cm</h3>

d = ut + ¹/₂at²

0.3 = (4)t + ¹/₂(-1.25)t²

0.3 = 4t - 0.625t²

0.625t² - 4t + 0.3 = 0

solve the quadratic equation using formula method;

t = 0.08 s

Learn more about velocity here: brainly.com/question/6504879

7 0

2 years ago

Rock X is released from rest at the top of a cliff that is on Earth. A short time later, Rock Y is released from rest from the s

frosja888 [35]

Answer:

C) True. S increases with time, v₁ = gt and v₂ = g (t-t₀) we see that for the same t v₁> v₂

Explanation:

You have several statements and we must select which ones are correct. The best way to do this is to raise the problem.

Let's use the vertical launch equation. The positive sign because they indicate that the felt downward is taken as an opponent.

Stone 1

y₁ = v₀₁ t + ½ g t²

y₁ = 0 + ½ g t²

Rock2

It comes out a little later, let's say a second later, we can use the same stopwatch

t ’= (t-t₀)

y₂ = v₀₂ t ’+ ½ g t’²

y₂ = 0 + ½ g (t-t₀)²

y₂ = + ½ g (t-t₀)²

Let's calculate the distance between the two rocks, it should be clear that this equation is valid only for t> = to

S = y₁ -y₂

S = ½ g t²– ½ g (t-t₀)²

S = ½ g [t² - (t²- 2 t to + to²)]

S = ½ g (2 t t₀ - t₀²)

S = ½ g t₀ (2 t -t₀)

This is the separation of the two bodies as time passes, the amount outside the Parentheses is constant.

For t <to. The rock y has not left and the distance increases

For t> = to. the ratio (2t/to-1)> 1 therefore the distance increases as time

passes

Now we can analyze the different statements

A) false. The difference in height increases over time

B) False S increases

C) Certain s increases with time, v₁ = gt and V₂ = g (t-t₀) we see that for the same t v₁> v₂

3 0

4 years ago

Explain the roles of the sympathetic division and parsympathetic division of the ANS in a fear response.(this is for psychology

tresset_1 [31]

Answer:

The parasympathetic division increases digestive activity and the sympathetic division decreases it. The Sympathetic Division of the ANS is responsible for mobilizing the body in response to situations that are threatening or otherwise exciting.

Explanation:

Have a great rest of your day
#TheWizzer

4 0

2 years ago

Read 2 more answers

Why are we not crushed by the weight of the atmosphere on our shoulders?

antiseptic1488 [7]

Answer:

Due to equal pressure in all the direction at a particular level in a fluid medium (Pascal's Law)

Explanation:

We are not crushed by the weight of the atmosphere because atmosphere is a fluid and we are immersed into it. So, according to the Pascal's law the the pressure a each point in a horizontal level is equal in all the direction irrespective of the orientation of a body.

Variation of pressure in term of the height of a fluid medium is given as:

$P=\rho.g.h$

$\rho=$ density of fluid

g = acceleration due to gravity

h = height of the free surface of the fluid from the immersed object.

And atmosphere has very less variation of pressure with change in height as it is a rare medium fluid and so for a human height there is very negligible variation of pressure at the heat of a human with respect to his toe.

5 0

3 years ago

Which of the following means that an image is real?