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2 years ago

I need help on 18,19,20 and 21

Physics

1 answer:

Dmitriy789 [7]2 years ago

8 0

When a relationship between two different things is shown in a fraction it is a ratio.

hope this helps :)

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A(n) ___ keeps a reaction from occurring by increasing the activation energy required for a reaction to occur. A. inhibitor B. c

skelet666 [1.2K]

Due to requirements i am typing this but the ans is a

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2 years ago

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A. How long does it take light to travel through a 3.0-mm-thick piece of window glass?

hodyreva [135]

Answer:

a) $1.517\times10^{-11}$ s

b) 3.41 mm

Explanation:

We take the speed of light, c = $3.0\times10^8$ m/s and the refractive index of glass as 1.517.

Speed = distance/time

Time = distance/speed

Refractive index, n = speed of light in vacuum / speed of light in medium

$n=\dfrac{c}{s}$

$s=\dfrac{c}{n}$

$t=\dfrac{d}{c/n}$

$t=\dfrac{dn}{c}$

$t=\dfrac{3\times10^{-3}\times1.517}{3.0\times10^8}$

$t=1.517\times10^{-11}$

We take the refractive index of water as 1.333.

Speed in water = speed in vacuum / refractive index of water

Distance = speed * time

$d=s\times t$

$d=\dfrac{c}{n_w}\times \dfrac{3\times10^{-3}\times1.517}{c}$

$d=\dfrac{3\times10^{-3}\times 1.517}{1.333}$

d = 3.41 mm

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3 years ago

While skateboarding at 19 km/h, Alana throws a tennis ball at 11 km/h to her friend Oliver. If Alana is the reference frame, the

nirvana33 [79]

Haven't taken physics but I would assume if her friend is standing in front of her that you would add up the speeds and get 30 km/hr.

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2 years ago

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A wire is wrapped 200 times around a hollow cylinder of cross-sectional area 12 cm2 and length 10 cm. Assuming the turns are spr

Sonja [21]

Answer:

The answer is 10.857mJ

Explanation:

The energy stored in this solenoid is given by the below mentioned equation,

$U = L*I^{2}/2$

where L the inductance of this solenoid is given by the below mentioned equation,

$L = u_{0} *N^{2}*A/L$

Plugging this into the energy equation you obtain the equation for the total energy stored in the magnetic field of the solenoid, given by,

$U = u_{0} *N^{2}*A*I^{2}/(2*L)$

where $u_{0}$ is the permeability of free space which equals to $u_{0} = 4*\pi *10^{-7} T.m/A$ . Plugging all the quantities into the above equation from the data in the question after converting to standard units. of meters instead of centimeters, we get for the energy stored in the coil,

$U = 10.857mJ$

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3 years ago

Which global concern is indirectly responsible for all of the others? A) pollution B) deforestation C) resource depletion D) hum

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D) human overpopulation

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2 years ago

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