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tamaranim1 [39]

3 years ago

11

You want to move a 4- kg bookcase to a different place in the living room. If u push with a force of 65 n and the bookcase accel

erates at 0.12 m/s2 what is the coefficient of kinetic friction between the bookcase and the carpet

1 answer:

IrinaK [193]3 years ago

7 0

Answer:

1.65

Explanation:

The equation of the forces along the horizontal direction is:

$F-F_f = ma$ (1)

where

F = 65 N is the force applied with the push

$F_f$ is the frictional force

m = 4 kg is the mass

$a=0.12 m/s^2$ is the acceleration

The force of friction can be written as $F_f = \mu R$ (2), where

$\mu$ is the coefficient of kinetic friction

R is the normal force exerted by the floor

The equation of forces along the vertical direction is

$R-mg=0$ (3)

since the bookcase is in equilibrium. Substituting (2) and (3) into (1), we find

$F-\mu mg = ma$

And solving for $\mu$ ,

$\mu = \frac{F-ma}{mg}=\frac{65-(4)(0.12)}{4(9.8)}=1.65$

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Answer:

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Explanation:

Given that,

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3 years ago

A ray of light traveling through air strikes a piece of diamond at an angle of incidence equal to 56 degrees. Calculate the angu

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Answer:

The angle of separation is $\Delta \theta = 0.93 ^o$

Explanation:

From the question we are told that

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The refractive index of red light in diamond is $n_r = 2.41$

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The wavelength of red light is $\lambda _r = 700nm = 700*10^{-9}m$

Snell's Law can be represented mathematically as

$\frac{sin \theta_i}{sin \theta_r} = n$

Where $\theta_r$ is the angle of refraction

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Now considering violet light

$sin \theta_r__{v}} = \frac{sin \theta_i}{n_v}$

substituting values

$sin \theta_r__{v}} = \frac{sin (56)}{2.46}$

$sin \theta_r__{v}} = 0.337$

$\theta_r__{v}} = sin ^{-1} (0.337)$

$\theta_r__{v}} = 19.69^o$

Now considering red light

$sin \theta_r__{R}} = \frac{sin \theta_i}{n_r}$

substituting values

$sin \theta_r__{R}} = \frac{sin (56)}{2.41}$

$sin \theta_r__{R}} = 0.344$

$\theta_r__{R}} = sin ^{-1} (0.344)$

$\theta_r__{R}} = 20.12^o$

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$\Delta \theta = \theta_r__{R}} - \theta_r__{V}}$

substituting values

$\Delta \theta =20.12 - 19.69$

$\Delta \theta = 0.93 ^o$

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Answer:

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