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3 years ago

11

If we're interested in knowing the rate at which light energy is received by a unit of area on a particular surface, we're reall

y trying to figure out the
A. incandescence.
B. luminous flux.
C. illuminance of a surface.
D. luminous intensity.

1 answer:

frosja888 [35]3 years ago

4 0

Answer: C. illuminance of a surface.

a) Incandescence: The phenomenon of light emission by a body as a result of high temperature.

B. Luminous flux : It is the quantity of the energy of the light emitted per second in all directions.

C. Illuminance of a surface :describes the quantity of light emitted by a light source or received at a surface.

D. luminous intensity : the quantity of visible light that a point source radiates in a given direction.

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RANGKAIAN RLC SERI PADA TEGANGAN BOLAK BALIK 220V R=80 OHM XL= 90 OHM XC = 30 OHM MAKA TEGANGAN PADDA INDUKTOR ADALAH???

Whitepunk [10]

Okay, 90% of this is nonsense besides the numbers maybe.

8 0

3 years ago

A person of mass 70 kg stands at the center of a rotating merry-go-round platform of radius 2.9 m and moment of inertia 900 kg⋅m

Cloud [144]

Explanation:

It is given that,

Mass of person, m = 70 kg

Radius of merry go round, r = 2.9 m

The moment of inertia, $I_1=900\ kg.m^2$

Initial angular velocity of the platform, $\omega=0.95\ rad/s$

Part A,

Let $\omega_2$ is the angular velocity when the person reaches the edge. We need to find it. It can be calculated using the conservation of angular momentum as :

$I_1\omega_1=I_2\omega_2$

Here, $I_2=I_1+mr^2$

$I_1\omega_1=(I_1+mr^2)\omega_2$

$900\times 0.95=(900+70\times (2.9)^2)\omega_2$

Solving the above equation, we get the value as :

$\omega_2=0.574\ rad/s$

Part B,

The initial rotational kinetic energy is given by :

$k_i=\dfrac{1}{2}I_1\omega_1^2$

$k_i=\dfrac{1}{2}\times 900\times (0.95)^2$

$k_i=406.12\ rad/s$

The final rotational kinetic energy is given by :

$k_f=\dfrac{1}{2}(I_1+mr^2)\omega_1^2$

$k_f=\dfrac{1}{2}\times (900+70\times (2.9)^2)(0.574)^2$

$k_f=245.24\ rad/s$

Hence, this is the required solution.

5 0

3 years ago

Need help girliess.

steposvetlana [31]

If I remember correctly, it is the 3rd answer choice.

8 0

3 years ago

How much pressure is applied to the ground

statuscvo [17]

Answer:

Pressure applied by the man= 285103.125 $Pa$ or 41.35 $lb/in^{2}$

Explanation:

Pressure is defined as the perpendicular force applied per unit area.

i.e. $Pressure=\frac{Force}{Area}$

Now, $Force= mg$

where, $m$ = mass of the body(man) = 93 kg

$g$ = acceleration due to gravity of Earth = 9.81 $m/{s^{2}}$

$Area$ covered is equal to the area of both stilts(a man generally stands on two feet)

therefore $Area=2(0.04)^{2}$ $m^{2}$

and putting in the values, we get,

$Pressure=\frac{93\times9.81}{2\times(0.04)^{2}}Nm^{-2}=285103.125Nm^{-2}$

Now we need to convert to our required units:

$1Nm^{-2}=1Pa\\1Pa=0.000145038lb/in^{2}$

(We can get the above result by individually converting kg to lb and meters to inches respectively)

Using the above relations we get,

$Pressure=285103.125Pa=0.000145038\times285103.125lb/in^{2}=41.35lb/in^{2}$

7 0

3 years ago

The Gulf Stream is an ocean current that runs from the southern tip of Florida up the eastern coast of the U.S. And ends in the

dmitriy555 [2]

Answer:

The Northern flowing stream will affect the coast of Europe by making climate of Western Europe and Northern Europe to be warmer than other areas that are located around the same latitude and this is simply because of the North Atlantic Current

Explanation:

The Northern flowing stream will affect the coast of Europe because the North Atlantic current causes the Gulf stream to be split into two ( 2 ) and the Northern stream which is a warm stream crossing over to Northern Europe. <em>The Gulf stream makes climate of Western Europe and Northern Europe to be warmer than other areas that are located around the same latitude and this is simply because of the North Atlantic Current</em>

7 0

3 years ago