2. What is the feather's initial velocity (before it is dropped) in m/s?

1. What layer of the Earth is<br> flowing, solid and plastic?

melisa1 [442]

Answer:

The mantle

Explanation:

The mantle is a plastic solid of varying densities which allow convection currents to flow molten rock towards the earth's surface resulting in volcanic activity, tectonic plate movement, earthquakes, and movement of continents.

5 0

3 years ago

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When a cold can of soda is insulated, the heat flow into the can on a hot day ____. a. increases c. stays the same b. decreases

telo118 [61]

The answer is decrease

4 0

3 years ago

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Part A Determine the absolute pressure on the bottom of a swimming pool 30.0 m by 8.7 m whose uniform depth is 1.8 m . Express y

Sphinxa [80]

Answer:

17.66 kPa

Explanation:

The volume of water in the swimming pool is the product of its dimensions

V = 30 * 8.7 * 1.8 = 469.8 cubic meters

Let water density $\rho = 1000 kg/m^3$ , and g = 9.81 m/s2 we can calculate the total weight of water in the swimming pool

$W = mg = \rho V g = 1000 * 469.8 * 9.81 = 4608738 N$

The area of the bottom

A = 30 * 8.7 = 261 square meters

Therefore the pressure is its force over unit area

$P = F/A = 4608738 / 261 = 17658 N/m^2$ or 17.66 kPa

7 0

4 years ago

How does fission and fusion affect an atoms nucleus differently?

Nata [24]

When a heavy nucleus breaks up into two or more fragments with the liberation of energy, the process is called fission.

When two light nuclei fuse together to form a comparatively heavy nucleus, the process is called fusion. Both processes are accompanied by release of energy.

The most common example of fission is the fission of Uranium nucleus, which absorbs a slow neutron and breaks into Barium, Krypton, a few neutrons and energy.

U(235)+neutron→Ba(139)+Kr(94)+3 neutrons+200 MeV

Each fission releases around 200 MeV of energy.

The fusion reaction is responsible for energy generated by stars.

Protons in the stars combine to form a Helium nucleus with the liberation of energy.

4 protons→Helium+2 positrons+ nuetirnos+ 26.7 MeV

Fusion reactions can happen only at very high temperatures, which is required ,so that the protons have enough kinetic energy to overcome their mutual electrostatic repulsion. The temperatures that can result in fusion are of the order 10^8 K is present in stars , hence stars generate energy by fusion.

However, such temperatures are difficult to maintain and control on Earth, and hence controlled fusion reaction is still not available commercially. Experiments are on , using large magnetic fields to contain the ions that undergo fusion, since no container can hold the nuclei while they undergo fusion.

Fusion is also called clean energy, since the byproducts of fusion are not radioactive, but many fission byproducts are generally radioactive.

5 0

3 years ago

A student applies a 10 N force to a wood block with a mass of 5 kg. The block is pushed across four different surfaces. The acce

Furkat [3]

The complete question is as follows: A student is subjected to a reaction force of 10 N northward from a 5 kg block while pushing the block over a smooth, level surface. Ignoring friction, what is the acceleration of the block?

Answer: The acceleration of the block is $2 m/s^{2}$ .

Explanation:

Given: Force = 10 N

Mass = 5 kg

It is known that force applied on an object is the product of mass and acceleration.

Mathematically, $F = m \times a$

where,

F = force

m = mass

a = acceleration

Substitute the values into above formula as follows.

$F = m \times a\\10 N = 5 kg \times a\\a = \frac{10}{5}\\= 2 m/s^{2}$

Thus, we can conclude that the acceleration of block is $2 m/s^{2}$ .

8 0

3 years ago