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3 years ago

What is the velocity in meters per second of a runner who runs exactly 110 m toward the beah in 72 seconds?

Physics

2 answers:

rjkz [21]3 years ago

8 0

B) 1.53 m/s towards the beach

Vitek1552 [10]3 years ago

6 0

Answer:

B). 1.53 m/s toward the beach

Explanation:

Velocity consists of a) a magnitude (the speed) and b) a direction.

The speed is given by the ratio between the distance covered and the time taken:

$v=\frac{110 m}{72 s}=1.53 m/s$

while the direction is given in the problem, it is the same as the displacement (toward the beach).

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What is the wavelength of light that is deviated in the first order through an angle of 13.1 ∘ by a transmission grating having

faltersainse [42]

Answer:

The wavelength of light is $4.53\times10^{-7}\ m$

Explanation:

Given that,

Angle = 13.1°

Number of slits = 5000

We need to calculate the wavelength of light

Diffraction of first order is defined as,

$d \sin\theta=n\lambda$ .....(I)

The separation of the slits

$d = \dfrac{1}{N}$

$d=\dfrac{1}{5000}$

$d=2\times10^{-6}\ m$

Now put the value in equation (I)

$2\times10^{-6}\sin13.1^{\circ}=\lambda$

Here, n = 1

$\lambda=4.53\times10^{-7}\ m$

Hence, The wavelength of light is $4.53\times10^{-7}\ m$

7 0

3 years ago

A plate of uniform areal density is bounded by the four curves: where and are in meters. Point has coordinates and . What is the

Natali5045456 [20]

The question is incomplete. The complete question is :

A plate of uniform areal density $\rho = 2 \ kg/m^2$ is bounded by the four curves:

$y = -x^2+4x-5m$

$y = x^2+4x+6m$

$x=1 \ m$

$x=2 \ m$

where x and y are in meters. Point $P$ has coordinates $P_x=1 \ m$ and $P_y=-2 \ m$ . What is the moment of inertia $I_P$ of the plate about the point $P$ ?

Solution :

Given :

$y = -x^2+4x-5$

$y = x^2+4x+6$

$x=1$

$x=2$

and $\rho = 2 \ kg/m^2$ , $P_x=1 \$ , $P_y=-2 \$ .

So,

$dI = dmr^2$

$dI = \rho \ dA \ r^2$ , $r=\sqrt{(x-1)^2+(y+2)^2}$

$dI = (\rho)((x-1)^2+(y+2)^2)dx \ dy$

$I= 2 \int_1^2 \int_{-x^2+4x-5}^{x^2+4x+6}((x-1)^2+(y+2)^2) dy \ dx$

$I= 2 \int_1^2 \int_{-x^2+4x-5}^{x^2+4x+6}(x-1)^2+(y+2)^2 \ dy \ dx$

$I=2 \int_1^2 \left( \left[ (x-1)^2y+\frac{(y+2)^3}{3}\right]_{-x^2+4x-5}^{x^2+4x+6}\right) \ dx$

$I=2 \int_1^2 (x-1)^2 (2x^2+11)+\frac{1}{3}\left((x^2+4x+6+2)^3-(-x^2+4x-5+2)^3 \ dx$

$I=\frac{32027}{21} \times 2$

$= 3050.19 \ kg \ m^2$

So the moment of inertia is $3050.19 \ kg \ m^2$ .

4 0

3 years ago

Instructions:Select the correct answer from the drop-down menu. The Longmenshan Fault is in China. This fault was created when t

lina2011 [118]

I say Reverse Fault, Hope this helps :)

3 0

3 years ago

PLEASE HURRY What is "a section of a chromosome that typically contains the code for a particular protein, which determines a sp

castortr0y [4]

Answer:

It is a gene!!

Explanation:

It is because RNA is referred to as a gene. Genes are contained in chromosones.

6 0

3 years ago

Which of the statements concerning light are true? The speed of light is the same no matter what material it is traveling throug

wel

Answer:

The statements that are true concerning light are the last three statements:

Its propagation direction is perpendicular to both the electric field and the magnetic field.

It moves at a constant speed through a vacuum.

The speed of light in matter is less than the speed of light in a vacuum.

Explanation:

Light is electromagnetic waves.

The properties of the electromagnetic waves were established by James Clerk Maxwell.

They included that they are the result of the oscillation of a magnetic field in phase with an electric field which are always is always perpendicular to each other.

Also, the electromagnetic waves propagate at right-angles to the direction of both the magnetic and the electric field, meaning that they are a type of transverse wave.

Thus, the second statement ("Its propagation direction is parallel to both the electric field and the magnetic field") is false, and the fourth statement ("Its propagation direction is perpendicular to both the electric field and the magnetic field") is true.

On the other hand, it is a postulate of the special theory of relativity that the speed of light is a constant (absolute value) in vacuum: nothing can travel faster than what light travels in vacuum. Thus, the fifth statement, "It moves at a constant speed through a vacuum" is true.

About the speed of light in matter, it is always less than the speed of light in vacuum. Thus, the first statement, "the speed of light is the same no matter what material it is traveling through", and the third statement "the speed of light in matter is greater than the speed of light in a vacuum" are false; while the last statement, "the speed of light in matter is less than the speed of light in a vacuum" is true.

The explanation on why the speed of light is less in a medium than in vacuum is related with the fact that at nanoscopic level the waves suffer polarization which means deviations from the straighi path, which makes that the net straight propagation is slower.

8 0

3 years ago