WILL MARK BRAINLIEST When the medium is uniform, how do light waves travel through it?

• Describe the importance of a commonly used measuring system. Be prepared to give two examples of why having a common system of

IrinaVladis [17]

Metric system. important because it saves us time due to the fact that we do not have to convert our units every time.

3 0

3 years ago

Why are some substances gases at room temperature but others are liquid or solid?

Otrada [13]

Answer:

The presence of strong intermolecular forces favors a condensed state of matter. liquid or solid), while very weak intermolecular interaction favor the gaseous state.

4 0

2 years ago

Please help on questions D AND E and please show working out as well so I can understand better thank you only QUESTIONS D AND E

tester [92]

Answer:

d. 87,500 J

e. 49,600 J

Explanation:

The total energy is the heat absorbed by the copper plus the heat absorbed by the water.

d)

E = m₁C₁ΔT + m₂C₂ΔT

E = (1 kg) (390 J/kg/°C) (10 °C) + (2 kg) (4180 J/kg/°C) (10 °C)

E = 87,500 J

e)

E = m₁C₁ΔT + m₂C₂ΔT

E = (2 kg) (390 J/kg/°C) (10 °C) + (1 kg) (4180 J/kg/°C) (10 °C)

E = 49,600 J

5 0

3 years ago

One end of a string is fixed. An object attached to the other end moves on a horizontal plane with uniform circular motion of ra

sveticcg [70]

Answer:

If both the radius and frequency are doubled, then the tension is increased 8 times.

Explanation:

The radial acceleration ( $a_{r}$ ), measured in meters per square second, experimented by the moving end of the string is determined by the following kinematic formula:

$a_{r} = 4\pi^{2}\cdot f^{2}\cdot R$ (1)

Where:

$f$ - Frequency, measured in hertz.

$R$ - Radius of rotation, measured in meters.

From Second Newton's Law, the centripetal acceleration is due to the existence of tension ( $T$ ), measured in newtons, through the string, then we derive the following model:

$\Sigma F = T = m\cdot a_{r}$ (2)

Where $m$ is the mass of the object, measured in kilograms.

By applying (1) in (2), we have the following formula:

$T = 4\pi^{2}\cdot m\cdot f^{2}\cdot R$ (3)

From where we conclude that tension is directly proportional to the radius and the square of frequency. Then, if radius and frequency are doubled, then the ratio between tensions is:

$\frac{T_{2}}{T_{1}} = \left(\frac{f_{2}}{f_{1}} \right)^{2}\cdot \left(\frac{R_{2}}{R_{1}} \right)$ (4)

$\frac{T_{2}}{T_{1}} = 4\cdot 2$

$\frac{T_{2}}{T_{1}} = 8$

If both the radius and frequency are doubled, then the tension is increased 8 times.

5 0

3 years ago

The sum of potential and kinetic energies in the particles of a substance is called

olganol [36]

Internal energy.

Explanation:

In any substance/object, the particles inside it (atoms/molecules) constantly move in random directions and with random speeds (this motion is called Brownian motion). As a result, the particles have some kinetic energy (which is proportional to the temperature of the substance). Moreover, the particles interact with each other due to the presence of electrostatic intermolecular forces, and as a result, the particles also have some potential energy.

The sum of the kinetic energies and potential energies of the particles in a substance is called internal energy.

6 0

4 years ago

Read 2 more answers