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3 years ago

Who invented the light emitting diode what purpose does it serve

Physics

1 answer:

vova2212 [387]3 years ago

3 0

Answer:Nick Holonyak

Oleg Losev

Shuji Nakamura invented it.

Explanation:

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A periodic transverse wave has an amplitude of 0.20 meter and a wavelength of 3.0 meters. If the frequency of this wave is 12 Hz

skelet666 [1.2K]

Answer:

36 m/s

Explanation:

The speed of wave is a product of wavelength and frequency, expressed as s=fw where f is frequency in Hz and w is wavelength. Wavelength is the distance between successive crests while frequency is also the reciprocal of time. Amplitude has no effect on the velocity of waves. Substituting frequency with 12 Hz and wavelength with 3 m then the speed will be

S=3*12=36 m/s

Therefore, the speed is 36 m/s

5 0

3 years ago

________ is the stress caused by forces that slip or slide one part of a material against another. a) Bending b) Shear c) Compre

jenyasd209 [6]

The best answer to fill in the blank would be B) Shear because shear stress is the process of where the composition of an object changes by sliding forces and so because of this, its a deformity.

8 0

4 years ago

Bob’s wife is in her third trimester of pregnancy. Bob’s _________ is/are likely to affect the health of his unborn baby.

madam [21]

Bob's wife or health is

7 0

3 years ago

A runner starts from rest and in 3 s reaches a speed of 8 m/s. If we assume that the speed changed at a constant rate (constant

Stells [14]

Answer:

The average speed of the runner is 4 m/s.

Explanation:

Hi there!

The average speed (a.s) is calculated by dividing the traveled distance (d) over the time needed to travel that distance (t):

a.s = d / t

So, let´s find the distance traveled in those 3 s. For that, we can use the equation of position of an object moving in a straight line with constant acceleration:

x = x0 + v0 · t + 1/2 · a · t²

Where:

x = position of the object at time t.

x0 = initial position.

v0 = initial velocity.

t = time.

a = acceleration.

If we place the origin of the frame of reference at the point where the runner starts, then, x0 = 0. Since the runner starts from rest, v0 = 0. So, the equation gets reduced to this:

x = 1/2 · a · t²

We have the time (3 s), so let´s find the acceleration. For that, we can use the equation of velocity of an object moving in a straight line with constant acceleration:

v = v0 + a · t

Where "v" is the velocity at a time "t". Since v0 = 0, then:

v = a · t

At t = 3 s, v = 8 m/s

8 m/s = a · 3 s

8/3 m/s² = a

So let´s find the position of the runner at t = 3 s (In this case, the position of the runner will be equal to the traveled distance):

x = 1/2 · a · t²

x = 1/2 · 8/3 m/s² · (3 s)²

x = 12 m

Now, we can calcualte the average speed:

a.s = d/t

a.s = 12 m / 3 s

a.s = 4 m/s

The average speed of the runner is 4 m/s.

4 0

3 years ago

A ladder 5.0 m long leans against a wall inside a spaceship. From the point of view of a person on the ship, the base of the lad

andriy [413]

Answer:

the angle the ladder makes with the floor as seen by an observer on Earth is 71.9°

Explanation:

Given the data in the question and as illustrated in the diagram below.

speed of the ship v = 0.90c

base of the ladder from the wall x₀ = 3.0 m

top of the later above the floor y = 4.0 m

we determine angle θ.

from the diagram,

tanθ = y/x₀

tanθ = y / x₀√( 1 - v²/c² )

we substitute

tanθ = 4.0 / 3.0√( 1 - ((0.9c)²/c²) )

tanθ = 4.0 / 3.0√( 1 - ((0.9²)c²/c²) )

tanθ = 4.0 / 3.0√( 1 - (0.9²) )

tanθ = 4.0 / 3.0√( 1 - 0.81 )

tanθ = 4.0 / 3.0√0.19

tanθ = 4.0 / 1.30766968

tanθ = 3.058876

θ = tan⁻¹( 3.058876 )

θ = 71.8965 ≈ 71.9°

Therefore, the angle the ladder makes with the floor as seen by an observer on Earth is 71.9°

3 0

3 years ago