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3 years ago

14

Please help on this one!! Please tell me why you got that answer.

1 answer:

Kaylis [27]3 years ago

7 0

The answer is A, that is the definition of power.

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What is the value of the following function when x = 0?

joja [24]

Answer:

b. y= -2

Explanation:

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4 years ago

Read 2 more answers

What are the differences between convex lens and convex mirrors ?

MaRussiya [10]

Answer:

The mirror is opaque while the lens is transparent

Explanation:

The lens is transparent throughout (lets light pass through), while the mirror reflects light. You are basically asking for the difference between a lens and a mirror

But how about the the behaviors of the convex mirror and convex lens? The convex lens will let light pass through and focus it on the other side of it. If you stand on one side of the lens, you can see what is on the other side of it. Think about a camera lens that's just curved!The convex mirror will reflect the light on the same side of it you'll basically will just see yourself but you'll look funny.

4 0

3 years ago

A light ray incident from medium 1 to medium 2, where n1>n2. When the incident angle exceed the critical angle ac, the refrac

vovikov84 [41]

Explanation:

(a)

Critical angle is the angle at the angle of refraction is 90°. After the critical angle, no refraction takes place.

Using Snell's law as:

$n_1\times {sin\theta_i}={n_2}\times{sin\theta_r}$

Where,

${\theta_i}$ is the angle of incidence

${\theta_r}$ is the angle of refraction = 90°

${n_2}$ is the refractive index of the refraction medium

${n_1}$ is the refractive index of the incidence medium

Thus,

$n_1\times {sin\ \theta_{critical}}={n_2}\times{sin\ 90^0}$

The formula for the calculation of critical angle is:

${sin\theta_{critical}}=\frac {n_2}{n_1}$

Where,

${\theta_{critical}}$ is the critical angle

(b)

No it cannot occur. It only occur when the light ray bends away from the normal which means that when it travels from denser to rarer medium.

7 0

4 years ago

You toss a ball straight up with an initial speed of 30m/s. How high does it go, and how long is it in the air (neglecting air r

Brut [27]

Explanation:

Given that,

A ball is tossed straight up with an initial speed of 30 m/s

We need to find the height it will go and the time it takes in the air.

At its maximum height, its final speed, v = 0 and it will move under the action of gravity. Using equation of motion :

v = u +at

Here, a = -g

v = u -gt

i.e. u = gt

$t=\dfrac{u}{g}\\\\t=\dfrac{30\ m/s}{9.8\ m/s^2}\\\\t=3.06\ s$

So, the time for upward motion is 3.06 seconds. It means that it will in air for 3.06×2 = 6.12 seconds

Let d is the maximum distance covered by it.

$d=ut-\dfrac{1}{2}gt^2$

Putting all values

$d=30(3.06)-\dfrac{1}{2}\times 9.8\times (3.06)^2\\\\d=45.91\ m$

Hence, it will go to a height of 45.91 m and it will in the air for 6.12 seconds.

8 0

3 years ago

A Boulder drops in the water and creates a wave with a period of 2s/cycle and a wavelength of .75 m/cycle. How fast is the wave

laiz [17]

Answer:

v = 0.375 m/s

Explanation:

Given that,

The wavelength of a wave is 0.75 m/cycle

The period of a wave is 2s/cycle

We need to find the speed of the wave. We know that,

$v=\dfrac{d}{t}$

Substitute all the values,

$v=\dfrac{0.75}{2}\\\\v=0.375\ m/s$

So, the speed of the wave is equal to 0.375 m/s.

7 0

3 years ago