All categories

2 years ago

What investigations allow for the control of variables

Physics

2 answers:

lina2011 [118]2 years ago

7 0

Most as long the hypothesis is a good answer and can be answered

PolarNik [594]2 years ago

3 0

I believe that the statement is true. Investigations allow for the control of variables. Changing variables will lead you to observations that may prove your hypothesis

You might be interested in

Help plss i just need it plss

Travka [436]

Answer:

ooh thanks but don't give me advise

4 0

3 years ago

A small grinding wheel has a moment of inertia of 4.0*10-5kgm2. What net torque must be applied to the wheel for its angular acc

kvv77 [185]

Hi there!

We can use the rotational equivalent of Newton's Second Law:

$\huge\boxed{\Sigma \tau = I \alpha}$

Στ = Net Torque (Nm)

I = Moment of inertia (kgm²)

α = Angular acceleration (rad/sec²)

We can plug in the given values to solve.

$\Sigma \tau = (4 * 10^{-5})(150) = \boxed{0.006 Nm}$

4 0

2 years ago

What is the single most important factor that determines why Earth (or almost any planet in the Solar System) experiences season

kirill [66]

Answer:

Planetary seasons are caused by two factors:

1. axial tilt and

2. variable distance from the sun

Explanation:

Earth's orbit is nearly circular and so has little effect on climate. It's our planet's axial tilt that causes almost all seasonal changes.

You can read further; Planetary seasons

6 0

2 years ago

Name a suitable plece of equipment that could be used to measure the length of the pool.

Fynjy0 [20]

Answer:

With a tape measure.

Explanation:

We can use a big tape measure, this tape is in the market and we can use the one with the proper length that lets us measure different sections of the total length of the pool.

4 0

3 years ago

At the very end of Wagner's series of operas The Ring of Nibelung, Brunnhilde takes the golden ring form the finger of the dead

Blababa [14]

Answer:

a) 404 m² b) apparent height = 7.5 m

Explanation:

This question is about refraction and total internal refraction.

Here I will take refractive index of air and water

$n_{air}=1\\ n_{water}=1.33=4/3$

Now let's look at the diagram I have attached here

At some angle A, the light from the ring (yellow point) under water will be totally internally refracted (B = 90°), which means that rays of light (yellow arrow) that make large enough angle A will not be able to escape from the water. Since we assumed that the ring is a point, there will be a critical cone of angle A with the ring at its apex which traces a circle of radius R on the surface of water, which, beyond this radius, no light could escape.

According to snell's law

$\frac{sin(B)}{sin(A)} = \frac{n_{water}}{n_{air}} = 4/3$

At critical angle B = 90°

$\frac{3)}{4}sin(B) = [tex]\frac{3}{4} sin(90^\circ ) = 0.75 = sin(A)$

Therefore

$A = 48.6^\circ$

With this, we can find the radius of the circle (refer to my diagram)

$h* tan (A) = R\\R =11.3 m$

And with that we can find the area

$A = \pi R^2=404\ m^2$

Additional Problem

For apparent depth from above, we can think that, since we are accustomed to seeing light at the speed of c in air, our brain interpret light from <em>any</em> source to be traveling at c. This causes light that originated under water, which has the speed of

$v_{water} = \frac{c}{n_{water}} = 0.75c$

to appear as if it has traveled with the same duration as light with speed c

In order for this to happen our brain perceive shortened length which is the apparent depth.

To put it in mathematical term

$t_{travel}=\frac{h_{apparent}}{v_{water}} =\frac{h}{c}$

So we get apparent depth

$h_{apparent}=0.75h = 7.5\ m$

4 0

3 years ago