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3 years ago

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A type of invisible matter whose gravity affects how galaxies move is called _____. A. dim matter B. dark matter C. black dwarfs

D. white dwarfs

1 answer:

mr_godi [17]3 years ago

5 0

Answer:

B

Explanation:

The answer is B

You might be interested in

A car travels 40 miles in 30 minutes.

lukranit [14]

Answer:

(a)Average velocity ,v =128.74 Km/hr

(b)Kinetic Energy , K=958546.875 Joule

(c)Distance, s=268.8m

(d)Acceleration, a= - 2.38 $m/s^2$

<u>Explanation</u>:

<u>Given</u>:

Distance travelled = 40 miles

Time taken = 30 minutes.

(A) The average velocity in kilometres/hour

Converting 40 miles into km ,

we know that,

1 mile = 1.60934

40 miles = 40 x 1.60934

so 40 miles = 64.3738 Km

similarly converting 30 minutes into hours

1 minute = $\frac{1}{60}hours$

30 minute = $\frac{30}{60}hours$

30 minute = $\frac{1}{2}hours$

Now

Average velocity = $\frac{Speed}{time}$

Substituting Values,

Average velocity = $\frac{64.3738}{\frac[1}{2}}$

Average velocity = $64.3738 \times 2$

Average velocity =128.74 Km/hr

(B) If the car weighs 1.5 tons, what is its If the car weighs 1.5 tons, what is its kinetic energy in joules (Note: you will need to convert your velocity to m/s)? in joules (Note: you will need to convert your velocity to m/s)?

Converting 1.5 tons into kg we get

1 ton = 1000 kg

so 1.5 ton =1500 kg

converting velocity to m/s

$128.74 \times \frac{5}{18}$

=>35.75 m/s----------------------------------------------------------(1)

kinetic energy K= $\frac{1}{2}mv^2$

Substituting the values,

K= $\frac{1}{2}1500(35.75)^2$

K= $\frac{1}{2}1500(1278.06)$

K= $\frac{1500 \times (1278.06)}{2}$

K= $\frac{1917093.75}{2}$

K=958546.875 Joule---------------------------------------------(2)

(c)When the driver applies the brake, it takes 15 seconds to stop. How far does the car travel (in meters) while stopping

Lets use Distance formula,

$S= ut+\frac{1}{2}at^2$

Substituting the known values,

$s= ut+\frac{1}{2}at^2$

$s= (37.75)(15)+\frac{1}{2}a(15)^2$

$s=566.25+\frac{1}{2}a(225)$

$s=566.25+\frac{(225a)}{2}$ -------------------------------------(3)

(D) What is the average acceleration of the car (in m/s2) during braking?

Using the formula

v=u +at

re arranging the formula we get,

$a = \frac{v - u}{t}$

Substituting the values

$a = \frac{0 - 35.75}{15}$

$a = \frac{- 35.75}{15}$

a= - 2.38 $m/s^2$ ----------------------------------------(4)

Now substituting 4 in 3 we get

$s=566.25+\frac{(225( - 2.38)}{2}$

$s=566.25+\frac{-535.5}{2}$

$s=536.25-267.75$

s=268.8m--------------------------------------------------------------(5)

4 0

3 years ago

what will happen to the brightness of the other bulbs in a series circuit if any of the bulbs were to burn out?

Ivenika [448]

Answer:

not work.

Explanation:

if u are saying in a series circuit...

if 1 build burns out and theres other bulbs the circuit wont work anymore.

6 0

3 years ago

Consider an alien on a planet with an acceleration of gravity equal to 20 m/sec^2. If the alien's mass is 10 kg, how much does t

mr_godi [17]

Answer:

the weight of alien is 200 newtons

Explanation:

The computation of the alien weight is shown below:

Given that

Acceleration = 20m/sec^2

And, the mass is 10 kg

So, the weight of alien is

= 20 × 10

= 200 newtons

hence, the weight of alien is 200 newtons

6 0

3 years ago

Which types of questions can most likely be answered through a scientific investigation?

Sindrei [870]

Subjective questions can be answered most likely through well-designed scientific investigations. Investigating peoples opinions or favorites does not involve any scientific investigations.

<h3>What are scientific investigation?</h3>

Scientific investigations include study on different natural phenomenon through well designed research methodologies. They include a preliminary hypothesis based on observations and various scientific records helps for reference.

Through well designed scientific experiments we can solve subjective questions and can be helpful in solving different environmental or social issues.

Peoples opinion or objective types questions are not targeted at scientific investigation, hence, option b is correct.

To find more on scientific investigations, refer here:

brainly.com/question/8386821

#SPJ1

4 0

1 year ago

Based on the mass and speed data, which object will have the greatest amount of kinetic energy

Alexus [3.1K]

The objects will have to be listed

5 0

2 years ago

Read 2 more answers