PLEASE I NEED SOME HELP!

{WILL GIVE (Brain lies t) TO FULL ANSWERS}

kap26 [50]

Answer:

1: surface temperature

2: red giant

3: The brightest stars are called supergiants. Star clusters are rich in stars just off the main sequence called red giants. Main sequence stars are called dwarfs.

4: A white dwarf is very dense

5: red giant

plz mark me as brainliest :)

4 0

2 years ago

Read 2 more answers

The image messed up but you get the point. Don't be mean and just answer to get the points, please and thank you.

Katarina [22]

Answer:

Answer is A, it will pass through to focal point after reflecting.

Explanation:

I had the same question in a test, Sorry that you had to do this question in middle school.

4 0

3 years ago

You stand on a bridge above a river and drop a rock into the water below from a height of 25 m. (Assume no air resistance)

Ilia_Sergeevich [38]

PART a)

here when stone is dropped there is only gravitational force on it

so its acceleration is only due to gravity

so we will have

$a = g = 9.8 m/s^2$

Part b)

Now from kinematics equation we will have

$y = v_i t + \frac{1}{2} at^2$

now we have

y = 25 m

so from above equation

$25 = 0 + \frac{1}{2}(9.8 )t^2$

$t = 2.26 s$

Part c)

If we throw the rock horizontally by speed 20 m/s

then in this case there is no change in the vertical velocity

so it will take same time to reach the water surface as it took initially

So t = 2.26 s

Part D)

Initial speed = 20 m/s

angle of projection = 65 degree

now we have

$v_x = vcos\theta$

$v_x = 20 cos65 = 8.45 m/s$

$v_y = vsin\theta$

$v_y = 20 sin65 = 18.13 m/s$

PART E)

when stone will reach to maximum height then we know that its final speed in y direction becomes zero

so here we can use kinematics in Y direction

$v_f - v_y = at$

$0 - 18.13 = (-9.8) t$

$t = 1.85 s$

so it will take 1.85 s to reach the top

5 0

2 years ago

Mr.Z holds 200 kg above his head for 5 seconds. What is the work done on the weights?

Alenkasestr [34]

m = mass held by mr. Z above his head = 200 kg

g = acceleration due to gravity = 9.8 m/s²

F = force applied by mr. Z to hold the mass

Using equilibrium of force , force equation is given as

F = mg

F = (200) (9.8)

F = 1960 N

Since the mass is not moved,

d = displacement of the mass = 0 m

we know that , work done is given as

W = F d

inserting the values

W = (1960) (0)

W = 0 J

8 0

3 years ago

A group of students painted four cans, placed 500 grams of water in each can, and measured the temperature of the water as shown

inna [77]

B.The water molecules in the black can had the largest increase in average kinetic energy.

<u>Explanation:</u>

Here, black painted can absorbs more heat than the other color painted cans.

Black color absorbs all the heat and didn't reflect anything back, so it absorbs the most heat.

White color reflects all the heat, so heat absorbed by the white can is least.

When the black can absorbs heat then the water molecules in the can gets its maximum amount of kinetic energy so that the water molecules in the can collide with each other and also along with the walls of the can here, and so the average kinetic energy increases.

7 0

3 years ago