Tasks

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

3 years ago

Which of the following choices is a single-replacement reaction? A. 2K + Br2 2KBr B. 2H2 + O2 2H2O C. Mg + FeO Fe + MgO D. C + 2

Otrada [13]

A single replacement reaction occurs when two different cations switch places to combine with the same anion. One element forms a compound while another element is released from the compound. In a single replacement reaction, or single displacement reaction, a single<span> uncombined element replaces another in a compound.

So you're answer is probably c.
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5 0

3 years ago

Use the work-energy theorem to determine the force required to stop a 1000 kg car moving at a speed of 20.0 m/s if there is a di

Vlad1618 [11]

Answer:

4.44 kN in the opposite direction of acceleration.

Explanation:

Given that, the initial speed of the car is, $u=20m/s$

And the mass of the car is, $m=1000 kg$

The total distance covered by the car before stop, $s=45m$

And the final speed of the car is, $u=0m/s$

Now initial kinetic energy is,

$KE_{i}=\frac{1}{2}mu^{2}$

Substitute the value of u and m in the above equation, we get

$KE_{i}=\frac{1}{2}(1000kg)\times (20)^{2}\\KE_{i}=20000J$

Now final kinetic energy is,

$KE_{f}=\frac{1}{2}mv^{2}$

Substitute the value of v and m in the above equation, we get

$KE_{f}=\frac{1}{2}(1000kg)\times (0)^{2}\\KE_{i}=0J$

Now applying work energy theorem.

Work done= change in kinetic energy

Therefore,

$F.S=KE_{f}-KE_{i}\\F\times 45=(0-200000)J\\F=\frac{-200000J}{45}\\ F=-4444.44N\\F=-4.44kN$

Here, the force is negative because the force and acceleration in the opposite direction.

6 0

2 years ago

Describe how visible light is used with solar photovoltaic panels to produce electricity

padilas [110]

Solar panels convert the sun's light into usable solar energy using N-type and P-type semiconductor material. When sunlight is absorbed by these materials, the solar energy knocks electrons loose from their atoms, allowing the electrons to flow through the material to produce electricity.

6 0

2 years ago

What does the law of conservation of momentum

babunello [35]

Answer:

the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision.

Explanation:

6 0

3 years ago