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2 years ago

14

Why are light-years more convenient than miles, kilometers, or astronomical units (au) for measuring the distances to stars and

galaxies? (select all that apply.)

1 answer:

Tomtit [17]2 years ago

5 0

Answer:

sEE BELOW

Explanation:

Well.....because the numbers are 'astronomical'....meaning VERY, VERY , VERY LARGE

You might be interested in

1.Explain frame of reference. How is it different when you are riding inside a car or standing by the highway?

galben [10]

Answer:

See explanation

Explanation:

A frame of reference simply refers to a set of coordinates which is used to determine the position and velocity of objects all the objects found in that particular frame. The person inside the car and standing by the highway are in different frames of reference.

Newtons first law of motion states that an object will continue to be at rest or in a state of uniform velocity until it is acted upon by an external force.

Newtons second law states that rate of change of momentum is directly proportional to the impressed force.

Newtons third law states that action and reaction are equal and opposite.

The action of applying brakes leads to an equal reaction of a sudden forward movement. Seat belts help to prevent the occupants of a car from being injured by the sudden stoppage of the car.

Force is simply defined as a push or pull.

Balanced forces do not lead to acceleration of a body but an unbalanced for leads to acceleration of a body.

strong nuclear force, electromagnetic force, weak nuclear force and gravity

Power is the rate of doing work while week is said to be done when the force applied moves a distance in the direction of the force. Power is defined as work/time.

8 0

3 years ago

A friend claims that throwing a baseball up towards the school roof illustrates gravitational potential energy transforming into

Cloud [144]

Answer:

The Statement is wrong because the reverse is the case as it is the kinetic energy that is being transformed to gravitational potential energy.

Explanation:

As your friend throws the baseball into the air the ball gains an initial velocity (u) and this makes the Kinetic energy to be equal to

$KE = \frac{1}{2} mu^2$

Here m is the mass of the baseball

Now as this ball moves further upward the that velocity it gained reduce due to the gravitational force and this in turn reduces the kinetic energy of the ball and this kinetic energy lost is being converted to gravitational potential energy which is mathematically represented as (m×g×h)

as energy can not be destroyed but converted to a different form according to the first law of thermodynamics

Looking a the formula for gravitational potential energy we see that the higher the ball goes the grater the gravitational potential energy.

4 0

4 years ago

An airplane is flying at a constant speed in a positive direction. It slows down when it approaches the airport where it's going

KatRina [158]

3.negative acceleration....

5 0

3 years ago

A nearsighted person wants to see an apple that is 7 meters away but can only clearly see objects that are at most 62 cm away fr

natulia [17]

Answer:

The power of the corrective lenses is 3.162 D.

Explanation:

Given that,

Object distance = 70 cm

Image distance = 62 cm

Distance between eyes and glasses = 2.5 cm

Eyeglasses made of diverging corrective lenses can help her to see the apple clearly

So now ,

Object distance from glass =70-2.5 = 67.5 cm

Image distance from glass = 62-2.5 = 59.5 cm

We need to calculate the focal length

Using formula for focal length

$\dfrac{1}{f}=\dfrac{1}{v}+\dfrac{1}{u}$

$\dfrac{1}{f}=-\dfrac{1}{59.5}-\dfrac{1}{67.5}$

$\dfrac{1}{f}=-\dfrac{508}{16065}\ cm$

We need to calculate the power of lens

Using formula of power

$P=\dfrac{100}{f}$

$P=-\dfrac{508}{16065}\times100$

$P=-3.162 \ D$

Negative sign shows the lens is diverging.

Hence, The power of the corrective lenses is 3.162 D.

6 0

3 years ago

How much power does it take to lift 70.0 N to 5.0 m high in 5.00 s?

lesantik [10]

Answer:

Power = 70 W

Explanation:

Given that,

Force, F = 70 N

Height, h = 5 m

Time, t = 5 s

We need to find the power of the object. We know that,

Power = work done/time

Put all the values,

$P=\dfrac{Fd}{t}\\\\P=\dfrac{70\times 5}{5}\\\\P=70\ W$

So, the required power is 70 W.

3 0

3 years ago