All categories

3 years ago

Melting butter is a physical change. Which best describes what is happening?

Physics

1 answer:

kati45 [8]3 years ago

3 0

Answer:

Option B

Explanation:

The butter forms a new arrangement of atoms i.e from solid to liquid

You might be interested in

if a 10kg object is lifted a distance of 10m from the rest what was the final velocity of the object?

Anastasy [175]

I think it will be 100 kg

5 0

3 years ago

A trained eye in the dark for an extended period of time may pick up a light stimulus from a light source, at the lowest radiate

frez [133]

Answer:

#_photons = 30 photons / s

Explanation:

Let's start by finding the energy of a photon of light, let's use the Planck relation

E = h f

the speed of light is related to wavelength and frequency

c = λ f

we substitute

E = h c /λ

E₀ = 6.63 10⁻³⁴ 3 10⁸/500 10⁻⁹

E₀ = 3.978 10⁻¹⁹ J

now let's use a direct proportion rule. If the energy of a photon is Eo, how many fornes has an energy E = 1.2 10⁻¹⁷ J in a second

#_photons = 1 photon (E / Eo)

#_photons = 1 1.2 10⁻¹⁷ /3.978 10⁻¹⁹

#_photons = 3.0 10¹

#_photons = 30 photons / s

3 0

2 years ago

You can increase the vapor pressure of a liquid by:

irga5000 [103]

Answer: Option (c) is the correct answer.

Explanation:

Vapor pressure is defined as the pressure exerted by vapors or gas on the surface of a liquid.

When we increase the temperature of a liquid substance then there will occur an increase kinetic energy of the molecules. As a result, they will move readily from one place to another.

Hence, liquid state of a substance will change into vapor state of the substance. This means that an increase in temperature will lead to an increase in vapor pressure of the substance.

Thus, we can conclude that you can increase the vapor pressure of a liquid by increasing temperature.

4 0

3 years ago

Water flows without friction vertically downward through a pipe and enters a section where the cross sectional area is larger. T

djverab [1.8K]

Answer:

$v_{2}$ will be less than $v_{1}$ and $P_{2}$ will be greater than $P_{1}$ .

Explanation:

As we know from the conservation of mass, the rate at which any amount of fluid mass ( $m_{1}$ ) is entering in a system is equal to the rate at which the same amount of fluid mass ( $m_{2}$ ) is leaving the system.

Rate of mass flow can be written as,

$m = \rho A v$

where $\rho$ is the density of the fluid, $A$ is the area through which the fluid is flowing and $v$ is the velocity of the fluid.

Now, according to the problem, as the density of the fluid does not change, we can write

$&& m_{1} = m_{2}\\&or,& \rho A_{1} v_{1} = \rho A_{2} v_{2}\\&or,& \dfrac{v_{2}}{v_{1}} = \dfrac{A_{1}}{A_{2}}$

where $A_{1}$ and $A_{2}$ are the cross-sectional areas through which the fluid is passing and $v_{1}$ and $v_{2}$ are the velocities of the fluid through the respective cross-sectional areas.

As according to the problem, $A_{2} > A_{1}$ , so from the above formula $v_{2} < v_{1}$ .

Also we know that fluid pressure is created by the motion of the fluid through any area. When the fluid gains speed, some of its energy is used to move faster in the fluid’s direction of motion. It causes in a lower pressure.

So, as in this case $v_{2} < v_{1}$ the pressure in the large cross-sectional area $P_{2}$ will be greater than the pressure $P_{1}$ in the small cross sectional area, i.e.,

$P_{2} > P_{1}$ .

6 0

4 years ago

In 1958 a large earthquake in Alaska produced a tsunami. What was the approximate height of the tsunami?

lilavasa [31]

The approximate height of the tsunami in Alaska in 1958 is 1720ft

6 0

3 years ago

Read 2 more answers