In winter why do water tanks start freezing from surface and not from bottom

What is the kinetic energy of a 200 kg satellite as it follows a circular orbit of radius 8x106m around the earth?

motikmotik

Given the equation for the Speed of a Satellite

v = SqRt{Gravitational Constant}{Mass of Earth} divided by the radius given in your problem

we have:

(square root whole term on right side)

v = G Me
———
r

so. (6.67x10^-11)(5.97x10^24)
___________________
(8.0x10^6)

v = 7055 m/s (which is reasonable)

so utilize the Kinetic Energy Formula

KE = 1/2mv^2

KE = 1/2(200)(7055)^2

KE = 4.977x10^9 J

4 0

3 years ago

Read 2 more answers

What happens to the particles in water as the water is heated and turns to vapor? (2 points)

Naddik [55]

Answer:

The particles will more likely to move faster since they are converted from a liquid to gas.

Rules for States of Matter:

1. Solid particles always are packed close together and don't have much space to move.

2. Liquid particles have space to move around but are still packed together, but not as close as solid.

3. Gas particles are moving freely, in fact they are in the air! Gas particles are free to move wherever. For example, the air has gas particles that are constantly bumping into each other.

Let me know if I am right =)

4 0

3 years ago

An insulated rigid tank contains 3 kg of H2O in the form of a saturated mixture of liquid and vapor at a pressure of 150 kPa and

Andre45 [30]

Answer:

change in entropy is 1.44 kJ/ K

Explanation:

from steam tables

At 150 kPa

specific volume

Vf = 0.001053 m^3/kg

vg = 1.1594 m^3/kg

specific entropy values are

Sf = 1.4337 kJ/kg K

Sfg = 5.789 kJ/kg

initial specific volume is calculated as

$v_1 = vf + x(vg - vf)$

$= 0.001053 + 0.25(1.1594 - 0.001053)$

$v_1 = 0.20964 m^3/kg$

$s_1 = Sf + x(Sfg)$

$= 1.4337 + 0.25 \times 5.7894 = 2.88 kJ/kg K$

FROM STEAM Table

at 200 kPa

specific volume

Vf = 0.001061 m^3/kg

vg = 0.88578 m^3/kg

specific entropy values are

Sf = 1.5302 kJ/kg K

Sfg = 5.5698 kJ/kg

constant volume so $v_1 - v_2 = 0.29064 m^3/kg$

$v_2 = v_1 = vf + x(vg - vf)$

$=0.29064 = x_2(0.88578 - 0.001061)$

$x_2 = 0.327$

$s_2 = 1.5302 + 0.32 \times 5.5968 = 3.36035 kJ/kg K$

Change in entropy $\Delta s = m(s_2 - s_1)$

=3( 3.36035 - 2.88) = 1.44 kJ/kg

8 0

3 years ago

A truck is traveling at 2.0 m/s. It slows to a stop at a constant rate over 3.00 s. How far does the car travel during those 3.0

earnstyle [38]

Answer:

During those 3.00 seconds before stopping, the car travels a distance of 6 m.

Explanation:

The simple rule of three is a tool that is used to quickly solve problems, where three pieces of information must be known, and one of them operates as an unknown to be known.

Two magnitudes are directly proportional if one magnitude increases the other also does it, and if the magnitude decreases the other in the same way.

Being a, b and c known data and x the unknown, the value that we want to know, the rule of three when the magnitudes are directly proportional is applied as follows:

a ⇒ b

c ⇒ x

So: $x=\frac{c*b}{a}$

In this case, knowing that a truck travels at 2 m/s, the rule of three applies as follows: if in 1 second the truck travels 2 m, in 3 seconds how much distance does it travel?

$distance=\frac{3 s*2 m}{1 s}$

distance= 6 m

During those 3.00 seconds before stopping, the car travels a distance of 6 m.

8 0

3 years ago

How does air resistance affect an object’s speed?

tatuchka [14]

When air resistance acts, acceleration during a fall will be less than g because air resistance affects the motion of the falling objects by slowing it down. Air resistance depends on two important factors - thespeed of the object and its surface area. Increasing the surface area of an object decreases its speed.

4 0

2 years ago