All categories

3 years ago

What do astronomers mean by light pollution?

1 answer:

7 0

Light pollution is influence of the light on earth (for example, street lighting) which interrupt observations. For example, if you are in a street during the night and street lights are turned on you won't see stars, but if lighting is turned off or if you go out of town you will see stars above.

You might be interested in

It is known that a shark can travel at a speed of 17 m/s. How far can a shark go in 8 seconds? (please show steps to how you got

Alex777 [14]

Answer:

136 meters.

Explanation: If it can go 17 meters a second, then after 8 seconds, it will go 136 meters. Multiple 17 by 8 to get your answer.

4 0

3 years ago

In a thundercloud there may be an electric charge of +40 C near the top of the cloud and -40 C near the bottom of the cloud. The

Ratling [72]

Answer:

Electric force, $F=-3.59\times 10^6\ N$

Explanation:

Given that,

Electric charge 1, $q_1=+40\ C$

Electric charge 2, $q_2=-40\ C$

Distance, $d=2\ km=2\times 10^3\ m$

To find,

The electric force between these two sets of charges.

Solution,

There exists a force between two electric charges and this force is called electrostatic force. It is equal to the product of electric charged divided by square of distance between them.

$F=k\dfrac{q_1q_2}{d^2}$

k is the electrostatic constant

$F=8.99\times 10^9\times \dfrac{40\times (-40)}{(2\times 10^3)^2}$

$F=-3.59\times 10^6\ N$

So, the electric force between these two sets of charges is $-3.59\times 10^6\ N$ .

5 0

3 years ago

A cyclist maintains a constant velocity of 6.1 m/s headed away from point A. At some initial time, the cyclist is 242 m from poi

KengaRu [80]

Answer:

553.1m

Explanation:

When an object moves at constant velocity we can express this movement like V=x/t, where V is the velocity, x is the displacement and t is the time spent on it.

In that way, the expression x=V.t give us the displacement from t=0s until t=51s, but we have to sum the initial distance from the point A.

x=242m +V.t = 242m + (6.1m/s x 51s) = 553.1m

7 0

3 years ago

Which statement about gravity is true?

SVETLANKA909090 [29]

Out of the given options, ‘it is described as a fundamental force and therefore does not depend on other forces’ is the true statement about gravity.

Answer: Option B

<u>Explanation: </u>

As we all know that there are four fundamental forces existing in the universe- Electromagnetic force, strong forces, weak forces and the gravitational force.

These are the forces that don’t depend on any other physical force to draw a considerable impact on the physical objects. The gravitational force can be defined as,

$F=G \times \frac{m_{1} m_{2}}{r^{2}}$

Where,

G = Gravitational Constant

$m_{1} , m_{2}$ = Masses of two substances under consideration

R = distance between the two substances.

Looking upon the formula of gravitational force we can easily estimate that the gravitational force relies on the mass of substances and the relative distance between them. There is no factor than the air friction that hinders the gravitational force and that too in a negligible amount.

5 0

3 years ago

Does it take 18 months for twins to be born, and 27 months for triplets, and so on?

Nezavi [6.7K]

No it all takes 9 or 10 months

3 0

3 years ago