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3 years ago

Which statement relates most directly to the second law?

Physics

2 answers:

alukav5142 [94]3 years ago

7 0

Statement three i do believe

jok3333 [9.3K]3 years ago

6 0

Answer: Option (2) is the correct answer.

Explanation:

According to second law of thermodynamics, all the energy of a system cannot be converted into useful work because some amount of energy will be lost.

For example, a machine will never convert its energy into 100% work as some of the energy of machine will be lost into the atmosphere.

Therefore, we can conclude that the statement some thermal energy is lost and some is used to do work, relates most directly to the second law.

You might be interested in

The moment of inertia for a 5500 kg solid disc is 12100 kg-m^2. Find the radius of the disc? (a) 2.111 m (b) 2.579 m (c) 1.679

Soloha48 [4]

Answer:

The radius of the disc is 2.098 m.

(e) is correct option.

Explanation:

Given that,

Moment of inertia I = 12100 kg-m²

Mass of disc m = 5500 kg

Moment of inertia :

The moment of inertia is equal to the product of the mass and square of the radius.

The moment of inertia of the disc is given by

$I=\dfrac{mr^2}{2}$

Where, m = mass of disc

r = radius of the disc

Put the value into the formula

$12100=\dfrac{5500\times r^2}{2}$

$r=\sqrt{\dfrac{12100\times2}{5500}}$

$r= 2.098\ m$

Hence, The radius of the disc is 2.098 m.

8 0

2 years ago

An electric ceiling fan is rotating about a fixed axis with an initial angular velocity magnitude of 0.300 rev/s . The magnitude

Salsk061 [2.6K]

1) 1.2 m/s

First of all, we need to find the angular velocity of the blade at time t = 0.200 s. This is given by

$\omega_f = \omega_i + \alpha t$

where

$\omega_i = 0.300 rev/s$ is the initial angular velocity

$\alpha = 0.895 rev/s^2$ is the angular acceleration

Substituting t = 0.200 s, we find

$\omega_f = 0.300 + (0.895)(0.200)=0.479 rev/s$

Let's now convert it into rad/s:

$\omega_f = 2\pi \cdot 0.479 rev/s=3.01 rad/s$

The distance of a point on the tip of the blade is equal to the radius of the blade, so half the diameter:

$r=\frac{0.800}{2}=0.400 m$

And so now we can find the tangential speed at t = 0.200 s:

$v=\omega_f r =(3.01)(0.400)=1.2 m/s$

2) $2.25 m/s^2$

The tangential acceleration of a point rotating at a distance r from the centre of the circle is

$a_t = \alpha r$

where $\alpha$ is the angular acceleration.

First of all, we need to convert the angular acceleration into rad/s^2:

$\alpha = 0.895 rev/s^ \cdot 2 \pi =5.62 rad/s^2$

A point on the tip of the blade has a distance of

r = 0.400 m

From the centre; so, the tangential acceleration is

$a_t = (5.62)(0.400)=2.25 m/s^2$

3) $3.6 m/s^2$

The centripetal acceleration is given by

$a=\frac{v^2}{r}$

where

v is the tangential speed

r is the distance from the centre of the circle

We already calculate the tangential speed at point a):

v = 1.2 m/s

while the distance of a point at the end of the blade from the centre is

r = 0.400 m

Therefore, the centripetal acceleration is

$a=\frac{1.2^2}{0.400}=3.6 m/s^2$

7 0

3 years ago

A bicycle tire of a radius of 0.44 m has a piece of gum stuck on its rim. What is the angle through which the tire rotates when

Karolina [17]

Based on the calculations, the angle through which the tire rotates is equal to 4.26 radians and 244.0 degrees.

<h3>How to calculate the angle?</h3>

In Physics, the distance covered by an object in circular motion can be calculated by using this formula:

S = rθ

<u>Where:</u>

r is the radius of a circular path.

θ is the angle measured in radians.

S is the distance.

Substituting the given parameters into the formula, we have;

1.87 = 0.44 × θ

θ = 1.87/0.44

θ = 4.26 radians.

Next, we would convert this value in radians to degrees:

θ = 4.26 × 180/π

θ = 4.26 × 180/3.142

θ = 244.0 degrees.

Read more on radians here: brainly.com/question/19758686

#SPJ1

6 0

1 year ago

The sales price of a product is $2 per unit; the variable cost is $1 per unit; and fixed costs total $1,000. how many units must

irakobra [83]

Answer:

<u><em>1000 units for breakeven</em></u>

Explanation:

Let x be the number of units sold at breakeven.

The total sales at the point would be $2x.

Variable costs would be $1x and fixed costs are $1000.

Total costs are = $1x + $1000

At breakeven: Sales = Costs

Sales =m Costs

$2x = $1x + $1000

$1x = $1000

x = 1000 units.

At 1000 units the sales are equal to the costs ("breakeven").

4 0

1 year ago

Water enters a typical garden hose of diameter 0.016 m with a velocity of 3 m/s. Calculate the exit velocity of water from the g

Vladimir79 [104]

Answer:

v₂ = 306.12 m/s

Explanation:

We know that the volume flow rate of the water or any in-compressible liquid remains constant throughout motion. Therefore, from continuity equation, we know that:

A₁v₁ = A₂v₂

where,

A₁ = Area of entrance pipe = πd₁²/4 = π(0.016 m)²/4 = 0.0002 m²

v₁ = entrance velocity = 3 m/s

A₂ = Area of nozzle = πd₂²/4 = π(0.005 m)²/4 = 0.0000196 m²

v₂ = exit velocity = ?

Therefore,

(0.0002 m²)(3 m/s) = (0.0000196 m²)v₂

v₂ = (0.006 m³/s)/(0.0000196 m²)

5 0

3 years ago