All categories

4 years ago

Which action can be explained by physics

Physics

2 answers:

Lunna [17]4 years ago

3 0

Dropping two objects and seeing them hit the ground at the same time

Juliette [100K]4 years ago

3 0

Answer:

<h2>"The pressure of blood exerted on the inner walls of the veins".</h2>

Explanation:

The given choices are

• the growth of fungus on a piece of bread .

• the mixing of sodium and chlorine to form common salt .

• the interactions between predators and prey in an ecosystem .

• the pressure of blood exerted on the inner walls of the veins.

The action that can be explained by physics is the last choice:

"The pressure of blood exerted on the inner walls of the veins".

The pressure of blood exerted onthe innter walls of the veins can be described by Continuity Equation which states the mass of a fluid which passes through certain volume is constant, that is, the mass of the fluid remains the same. A deduction of the Continuity Equation is when the fluid passes through greater areas, its pressure is lower and when the fluid passes through sameller areas, its pressure is higher.

That principal can be used to described blood pressure, for example, when people have too much fat, their blood pressure is higher, that is because the area of the veins is smaller, which increases the pressure of the fluid (the blood).

Therefore, the only action that can be explained by physics is the last one.

You might be interested in

If a net force acts on an object the object will change speed, direction or shape

DanielleElmas [232]

Only the speed will change because it is in motion

5 0

4 years ago

3 PHYSICAL SCIENCE: In order to figure out what is in a sealed box, you perform some tests. The box seems heavy for its size and

rjkz [21]

Some sort of magnetic metal

Metals are heavier per cubic unit than other materials such as air or water, and also are much more magnetic than other materials

7 0

4 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)