The power of a machine is 6000 W. This machine is scheduled for design improvements. Engineers have reduced the

How many common phases of matter are there? A. Four B. Eight C. Five D. Three

kirill115 [55]

three
SLG
solid
liquid
gas

3 0

3 years ago

A ball is dropped from rest from the top of a building of height h. At the same instant, a second ball is projected vertically u

lawyer [7]

Answer:

Find the answer in the explanation

Explanation:

Given that a ball is dropped from rest from the top of a building of height h. At the same instant, a second ball is projected vertically upward from ground level, such that it has zero speed when it reaches the top of the building.

a. When do the two balls pass each other?

The the balls will pass each other before the second ball reach half of the height of the building. Because the velocity of the second ball decreases as it goes upwards while the velocity of the first ball increases as it moves downwards

b. Which ball has greater speed when they are passing?

The first ball of course because the velocity of the second ball decreases as it goes upwards while the velocity of the first ball increases as it moves downwards

c. What is the height of the two balls when they are passing?

Taking the height from the bottom of the building upward

Since the two balls meet at a certain point, they will both have the same height.

7 0

3 years ago

An ideal air-filled parallel-plate capacitor has round plates and carries a fixed amount of equal but opposite charge on its pla

Vikentia [17]

Answer:

The new energy density is same as initial energy density u0 as it is independent of plate dimensions

Explanation:

As we know that energy density is total energy per unit volume

so we know that isolated plates of capacitor is placed here

$C = \frac{\epsilon_0 A}{d}$

here we have energy density given as

$u = \frac{Q^2}{2(\epsilon_0 A/d)} Ad$

so we have

$u = \frac{Q^2d^2}{2\epsilon_0}$

so it is independent of the dimensions of the plate while total charge on the plates is constant always

so energy density will not change and remains the same

8 0

3 years ago

The CEO, ellen misk, left her martian office but accidentally left a cylindricall can of coke (3.1 inches in diameter, 5.42 inch

iren2701 [21]

Answer:

Specific Gravity = 0.378

Explanation:

First, we will find the force exerted by the can on the table. This force will be equal to the weight of the can:

Pressure = Force/Area = Weight/Area

Weight = Pressure*Area

where,

Area = πdiameter²/4 = π[(3.1 in)(0.0254 m/1 in)]²/4 = 4.8 x 10⁻³ m²

Weight = (510 N/m²)(4.8 x 10⁻³ m²)

Weight = 2.48 N

Now, the weight is given as:

Weight = mg

2.48 N = m(9.8 m/s²)

m = (2.48 N)/(9.8 m/s²)

m = 0.25 kg

Now, we calculate volume of can:

Volume = (Area)(Height) = (4.8 x 10⁻³ m²)(5.42 in)(0.0254 m/1 in)

Volume = 6.6 x 10⁻⁴ m³

Hence, the density of can will be:

Density of Can = m/Volume = 0.25 kg/6.6 x 10⁻⁴ m³

Density of Can = 378.32 kg/m³

So, the specific gravity of Can will be:

Specific Gravity = Density of Can/Density of Water

Specific Gravity = (378.32 kg/m³)/(1000 kg/m³)

<u>Specific Gravity = 0.378</u>

8 0

3 years ago

A brick sits on the top of a hill with a gravitational potential energy of 245 J. To determine the gravitational potential of th

Bogdan [553]

Answer:

The mass of the object, its acceleration due to gravity and the distance between the top of the hill and the ground level.

Explanation:

gravitational potential energy is the energy possessed by a body under influence of gravitational force by virtue of its position.

In order to determine the gravitational potential energy of the brick, we must know the mass (m) of the brick, its acceleration due to gravity (g) since it is acting under the influence of gravitational force and the distance between the top of the hill and the ground level. (The height).

Potential energy of a body is calculated as mass × acceleration due to gravity × height.

5 0

3 years ago