All categories

3 years ago

1. Simplify the following expression 8-6/4-12+3^2

Physics

1 answer:

DanielleElmas [232]3 years ago

5 0

Answer:

-5/2

Explanation:

8-6/4-12+3^2

8-6/4-12+9

2/4-12+9

LCM =4

(2-48+36)/4

(-46+36)/4

-10/4

-5/2

You might be interested in

An engine draws energy from a hot reservoir with a temperature of 1250 K and exhausts energy into a cold reservoir with a temper

bixtya [17]

Answer:

a. $P=18.61\ W$

b. $\eta_c=0.6976=69.76\%$

c. $\eta=0.4718=47.18\%$

Explanation:

Given:

temperature of the hotter reservoir, $T_H=1250\ K$

temperature of the colder reservoir, $T_C=378\ K$

heat absorbed by the engine, $Q_H=1.42\times 10^{5}\ J$

heat rejected to the cold reservoir, $Q_L=7.5\times 10^4\ J$

time duration of the energy transfer, $t=1\ hr=3600\ s$

<u>Now the work done by the engine:</u>

Using energy conservation,

$W=Q_H-Q_L$

$W=14.2\times 10^4-7.5\times 10^4$

$W=6.7\times 10^4\ J$

<u>Hence the power output:</u>

$P=\frac{W}{t}$

$P=\frac{6.7\times 10^4}{3600}$

$P=18.61\ W$

$\eta_c=1-\frac{T_L}{T_H}$

$\eta_c=1-\frac{378}{1250}$

$\eta_c=0.6976=69.76\%$

now actual efficiency:

$\eta=\frac{W}{Q_H}$

$\eta=\frac{6.7\times 10^4}{1.42\times 10^{5}}$

$\eta=0.4718=47.18\%$

6 0

4 years ago

A solution is a homogeneous mixture of one or more solutes dissolved in a solvent. A specific volume of solvent is only able to

Luba_88 [7]

<h3><u>Answer;</u></h3>

C. Supersaturated

<h3><u>Explanation</u>;</h3>

Solutions are homogeneous mixtures that are created by mixing a solute and a solvent. Solute is the substance present in smaller amounts that dissolves in a solvent such as water which is the substance present in larger amount.
A solution, can be<u> unsaturated, saturated or supersaturated. An unsaturated solution</u> is a solution that contains less solute that can be dissolved, it doesn't contain the maximum amount of solute.
<u>A saturated solution</u> is a solution containing the maximum amount of solute that can be dissolved at a given temperature. Any additional solute will remain undissolved in the container.
<u>A supersaturated solution</u> is a solution created when a solution is carefully cooled because it contains more solute than the solubility allows.