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2 years ago

How long does it take light to reach Earth from an object on light-year away?

Physics

1 answer:

stepladder [879]2 years ago

5 0

Answer:

The short answer is that it takes sunlight an average of 8 minutes and 20 seconds to travel from the Sun to the Earth.

Explanation:

how long does it take sunlight to reach Earth? This sounds like a strange question, but think about it. Sunlight travels at the speed of light. Photons emitted from the surface of the Sun need to travel across the vacuum of space to reach our eyes. If the Sun suddenly disappeared from the Universe (not that this could actually happen, don't panic), it would take a little more than 8 minutes before you realized it was time to put on a sweater.

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Application - You have two objects that you want to push the same distance (5 meters) across the floor. The objects have differe

Mamont248 [21]

I see you're in Middle School, so I've got a hunch that they want you
to say "the dresser because it has more mass". But that's a poor
answer, to a poor question.

The fact is that there's no way to tell.

The force it takes to move either object across the floor does NOT really
depend on just its mass. It depends on both the object's mass AND the
friction between the object and the floor. And THAT depends on the shape
of the feet where they touch the floor, and what kind of material the feet and
the floor are made of.

So it seems to me that we really don't have enough information to answer
the question with.

But again, I suspect that the answer they want is "the dresser because
it has more mass".

8 0

3 years ago

What pressure is exerted on the bottom of a 0.500-m-wide by 0.900-m-long water tank that can hold 50.0 kg of water by the weight

svetoff [14.1K]

Answer:

1088.9N/m2

Explanation:

Calculation for What pressure is exerted

First step is to find the area of bottom of the tank using formula

Area=Width*breadth

Let plug in the formula

Area=0.5*0.9

Area=0.45m2

Now let calculate what pressure is exerted using this formula

Pressure=Force/Area

Where,

Force=Mass *Gasoline

Area=Width of the tank* Length of the tank

Let plug in the formula

Pressure=50*9.8/0.5*0.9

Pressure=490/0.45

Pressure=1088.9N/m2

Therefore What pressure is exerted is 1088.9N/m2

3 0

3 years ago

A soccer ball is kicked from the ground with an initial speed v at an upward angle θ. A player a distance d away in the directio

Nady [450]

Answer:

The speed of player is given by

$V=\frac{2v^{2} 2sin\alpha.cos\alpha-gd }{2vsin\alpha}$

Explanation:

The time of flight for a projectile motion is given by

$T=\frac{2vsin\alpha }{g}$ (i)

where t is the time of flight, v is the initial speed, and α is the angle.

Now the person must also reach the impact point of ball in the same time as above.

Now the total distance D the player needs to cover is basically R horizontal range of projectile minus the distance d, range R is given by,

$R=\frac{2v^{2} sin2\alpha }{g}$

Now the distance the player must cover is given by

D= R-d

D= $\frac{2v^{2} sin2\alpha }{g}$ - d

$D=\frac{2v^{2}sin2\alpha-gd}{g}$ (ii)

Now the average speed of player is given by

$V=\frac{D}{T}$ (iii)

Replacing the values of D and T from eq. (i) and (ii) in eq. (iii).

$V=\frac{\frac{2v^{2} sin2\alpha-gd }{g}}{\frac{2vsin\alpha }{g} }$

$V=\frac{2v^{2} 2sin\alpha.cos\alpha-gd }{2vsin\alpha}$

3 0

3 years ago

Why unit of pascal is called derived unit?

Annette [7]

Answer:

This is because it is derived from newtons and metres as shown in the expression;

Explanation:

$pressure = \frac{force}{area} \\ P= \frac{F}{A} \\ P= \frac{newtons}{ {m}^{2} } \\ = pascals$

5 0

3 years ago

Read 2 more answers

The segment on the left has diameter 1.6 mm, and each of the segments on the right has diameter 0.4 mm. Assume the blood can be

oksian1 [2.3K]

Answer:

Explanation:

The flow entering the first segment will be the same as the flow exiting the second segment, and in both cases it will be equal to the velocity multiplied by the area of the segment. If $Flow_{a} = Flow_{b}$ and Flow = VxA, then you have:

$V_{a} x A_{a} = V_{b} x A_{b}$ (1)

You can also calculate the transversal area of each segment, because blood vessels are cylinders and you know each segment's diameter. The formula to calculate this is:

$A = \pi /4 x d^{2}$