How can water be in gas form at 80 degrees

Does uniform acceleration means increasing acceleration?

tatiyna

Yes. It means that the acceleration increases at a constant rate, for example 3 mph every second.

5 0

3 years ago

Hawks and gannets soar above the ground and, when they spot prey, they fold their wings and essentially drop like a stone. They

denis-greek [22]

Answer:

v = 54.2 m / s

Explanation:

Let's use energy conservation for this problem.

Starting point Higher

Em₀ = U = m g h

Final point. Lower

$Em_{f}$ = K = ½ m v²

Em₀ = Em_{f}

m g h = ½ m v²

v² = 2gh

v = √ 2gh

Let's calculate

v = √ (2 9.8 150)

v = 54.2 m / s

3 0

3 years ago

An airplane engine starts from rest; and 2 seconds later, it is rotating with an angular speed of 300 rev/min. if the angular ac

elena-s [515]

First of all, we need to convert the angular speed from rev/min into rev/s:

$\omega_f=300 rev/min=5 rev/s$

The angular acceleration is the variation of angular speed divided by the time:

$\alpha=\frac{\omega_f-\omega_i}{t}=\frac{5 rev/s-0}{2 s}=2.5 rev/s^2$

And this is constant, so we can use the following equation to calculate the angle through which the engine has rotated:

$\theta(t)=\frac{1}{2}\alpha t^2 =\frac{1}{2}(2.5 rev/s^2)(2 s)^2=5 rev$

so, 5 revolutions.

3 0

3 years ago

What is the mass of a sample of water that takes 2000 kJ of energy to boil into steam at 373 K? The latent heat of vaporization

GREYUIT [131]

Answer : The mass of a sample of water is, 888.89 grams

Explanation :

Latent heat of vaporization : It is defined as the amount of heat energy released or absorbed when the liquid converted to vapor at atmospheric pressure at its boiling point.

Formula used :

$q=L\times m$

where,

q = heat = 2000 kJ = $2\times 10^6J$ (1 kJ = 1000 J)

L = latent heat of vaporization of water = $2.25\times 10^6J/kg$

m = mass of sample of water = ?

Now put all the given values in the above formula, we get:

$2\times 10^6J=(2.25\times 10^6J/kg)\times m$

$m=0.88889kg=888.89g$ (1 kg = 1000 g)

Therefore, the mass of a sample of water is, 888.89 grams

3 0

3 years ago

A 51-kg packing crate is pulled with constant speed across a rough floor with a rope that is at an angle of 37.0Â° above the hor

fiasKO [112]

work is done by the pulling force which is same as the tension force in the rope. the net work done is zero for the crate since crate moves at constant velocity. but there is work done by the tension force which is equal in magnitude to the work done by the frictional force.

T = tension force in the rope = 115 N

d = displacement of the crate = 7.0 m

θ = angle between the direction of tension force and displacement = 37 deg

work done on the crate is given as

W = F d Cosθ

inserting the values given above

W = (115) (7.0) Cos37

W = 643 J

3 0

3 years ago