You observe a star system for many weeks. The light curve does not show significant changes in brightness, but a series of spectra show a spectral feature that cyclically appears as one absorption line, then two, then one again, and so on. Is this a binary system

Answer:

Hi, Im Jenna! Here is ur ansswer Pls mark as braijnliest

Explanation:

solution.

The formula for linear expansivity is

α = (If – If) / If (0f – 0i ) is used to determine the linear expansivity

If – final length,

I – initial length

0f – final tempt.

0i – initial tempt.

(b) (ii)

I = 3 m

0 = 29oC

02 = 41oC

α = 1.0 x 10 k-1

using safety gap = change in length

Δ l = α I Δ Θ

1 x I0-5 x 3.0 x (41 – 29) = 3.6 x 10-3 m = 0.0036

Answer:

Since energy means capacity to do work, when stone is in ground level, it has 0 work because it doesn't covered any distance but when stone lifted at a certain height , it covered a certain distance and work is done. Thus same stone has energy when it is lifted at a height .

Explanation:

Answer:

1N

Explanation:

F=ke

k=10N/m

e=0.1m

F=10*0.1

F=1N

Answer:

B 7.5mph/s

Explanation:

use change in y/ change in x

The amount of work done by the fork-lift truck in lifting the crate is 2,195.2 Joules.

Given the following data:

Scientific data:

To calculate the amount of work done by the fork-lift truck in lifting the crate:

In Science, work done is generally calculated by multiplying force and the vertical distance or displacement experienced by an object.

Mathematically, work done is given by the formula:

[tex]Work\;done = force \times displacement = mgh[/tex]

Substituting the given parameters into the formula, we have;

[tex]Work\;done = 64 \times 9.8 \times 3.5[/tex]

Work done = 2,195.2 Joules.

Read more on work done here: brainly.com/question/22599382

Let's see why g is 0 at centre of earth

[tex]\\ \rm\rightarrowtail g\propto \dfrac{1}{h}[/tex]

Means g is indirectly proportional to height of object.

At centre h=0

And at centre the distance from top of earth surface is equal in opposite directions from centre.

So

[tex]\\ \rm\rightarrowtail F_{net}=0[/tex]

Hello! Answer is below.

The center of the earth has no gravity, at all, since its pulling on you in all other directions (hints to why you can float if you were in a room/ spaceship, since there are so many massive objects).Gravity pulls us because there are massive objects that exert a gravitational force on everything around them. The further away the object is, the weaker the force is. For exapmple, if all those massive objects dissapeared, we would be able to walk freely. Meaning,we could walk the way we do on earth.

Hope this helps.

-Natalia.

Answer:

A and B

Explanation:

got it right

Answer:

Is there a target date for the hiring decision?

What is your preferred method for follow-up contact?

An ohmic resistor is a resistor that obeys Ohm's law V = IR (voltage = current x resistance). Therefore, if the voltage in such element is increased by n number of times, by the same number n has to increase the current.

[tex] \\ [/tex]

hope it helps:)

Ohmic resistors are materials that obeys ohms law.

An ohmic resistor is a material that obey's ohms law. This material does not allow passage of electricity through it.

V = IR

where;

Thus, ohmic resistors are materials that obeys ohms law.

Learn more about ohms law here: https://brainly.com/question/231741

Answer:

the layers of atmosphere are heated through radiation and convection.

Explanation:

Answer:

[tex]2 \: cm[/tex]

Explanation:

Total diameter:

[tex]12 - 4 = 8 \: cm[/tex]

Diameter of 1 ball:

[tex] \frac{8}{4} = 2 \: cm[/tex]

Answer:

a reflected sound wave completely bounces off an object and diffraction occurs when there is an opening in a wall and only the waves that can fit through the wall go and then the waves start to expand again after going through the hole.

Explanation:

Answer:

By applying relative small force to the smaller piston

Explanation:

If a car sits on top of the large piston, it can be lifted by applying a relatively small force to the smaller piston, the ratio of the forces being equal to the ratio of the areas of the pistons

The velocity of the fourth piece after the explosion is 118.5 m/s at 14.7⁰ east of north.

The principle of conservation of linear momentum states that the sum of the initial momentum is equal to sum of final momentum.

Initial momentum of the bomb before explosion is equal to the final momentum of pieces of bomb after explosion.

Pi = Pf

0 = P₁ + P₂ + P₃ + P₄

0 = mv₁ + mv₂ + mv₃ + mv₄

0 = v₁ + v₂ + v₃ + v₄

Consider x-y plane for the velocity of the piece of bomb;

[tex]0 = (v_1x + v_1y) + (v_2x + v_2_y) + (v_3x + v_3_y) + (v_4_x + v_4_y)\\\\0 = (0 - 50y) + (-80x + 0) + (-40cos30x + 40sin30y) + (v_4_x + v_4_y)\\\\0 = -50y -80x - 34.64x + 20y + v_4_x + v_4_y\\\\0 = -30y - 114.64x + v_4_x + v_4_y \\\\v_4_x + v_4_y = 114.64x + 30y\\\\|v_4| = \sqrt{114.64^2 + 30^2} \\\\|v_4| = 118.5 \ m/s\\\\tan(\theta ) = \frac{30}{114.64} \\\\tan(\theta) = 0.262\\\\\theta = tan^{-1} (0.262)\\\\\theta= 14.7 \ ^0[/tex]

Thus, the velocity of the fourth piece is 118.5 m/s at 14.7⁰ east of north.

Learn more about conservation of linear momentum here: https://brainly.com/question/7538238

Answer:

A car weighing 2500 kg and travelling at 15 m/s stops at a distance of 25 m deceleration uniformly. What is the force exerted on it by the brakes?

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5 Answers

Naren Nagarajan

, Cambridge Examinations Officer at Kasiga School, Dehradun (2008-present)

Answered 3 years ago · Author has 1.1K answers and 1.9M answer views

(a) W= Fd ( energy = force x distance )

(b) KE = .5 m v*v ( Kinetic energy of the car )

KE =0.5 * 2500 * 225KE =281250 Joules

Using (a) , Reducing kinetic energy to zero over 25 m

281250 = F * 25

F = 281250 /25

F = 11250 N

To check or use a different method …..

v^2 = u^2 +2as ( Third equation of motion )

2as = v^2 -u^2 ( v = 0 and U = 15 )

as = -225/2

a = - 225/2 * 25

a= - 225/50

a= - 4.5 m sec ^ -2

F = ma

F = 2500 * - 4.5

F = - 11250 N ( the negative sign indicates that the force is opposite in direction to the motion of the car )

The answer is correct since both values for F are equal.

Answer:

Ok so there are many ways to go at this.

you can get a zip lock bag and put a bunch of plastic around the egg inside the bag. (image down below)

Just anything to slow down the descent speed.

Cushion the egg so that something other than the egg itself absorbs the impact of landing.

Explanation:

W= mg × d × cosx

W= 12 × 10 × 2.2 × (-1)= -264 J

I hope it helps you

please mark brainliest ♡

Answer:

space

Explanation:

I got it right on E d i n u i t y

A space telescope called the Hubble was put into low-Earth orbit. Therefore, Hubble telescope is located in space.

A space telescope called the Hubble was put into low-Earth orbit around 1990 and continues to be in use today. Although it wasn't the initial space telescope, it is one of the biggest and most useful ones. It is famous for being both an essential scientific instrument and a public relations success for astronomy.

One of NASA's Big Observatories, the Hubble telescope being dedicated after astronomer Edwin Hubble. Hubble's targets are chosen by the Space Telescope Scientific Institute, which also handles the data processing, while the spacecraft is managed by the Goddard Space Flight Center at NASA. Hubble telescope is located in space.

Therefore, Hubble telescope is located in space.

To know more about Hubble telescope, here:

https://brainly.com/question/30246219

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Inertia refers to the tendency of a body to resist changes.

It is the property of a body to resist change.

A moving body will continue moving until a force acts on it. Unless the acting force is big enough to overcome the inertia of the body, the body will continue moving.

Also, a body at rest will continue resting unless a force big enough to overcome the inertia force is used to displace it.

More on inertia can be found here: https://brainly.com/question/1358512

Answer:

inertia, property of a body by virtue of which it opposes any agency that attempts to put it in motion or, if it is moving, to change the magnitude or direction of its velocity. Inertia is a passive property and does not enable a body to do anything except oppose such active agents as forces and torques.

Answer:

I believe the answer is 45

Answer with explanation

a) Formula to find the current that passes through a circuit is :

Given that,

Voltage = 45V

Resistance = 39Ω

Current =?

Let us find it now.

V = I × R

45V = I × 39Ω

Divide both sides by 39.

1.153A = I = Current

b) Formula to find the energy is:

            = 45V × 1.153A × ( 5 × 60)s

            = 15565.5 J

            = 15.5655kJ

The density of the block is mathematically given as

[tex]\phi=8e-4[/tex]

Question Parameters:

50 cm by 100 cm by 200 cm has a mass of 8000 g.

Density is simply defined as the mass per unit volume of a material or substance

where

Volume and Mass are factors of density

Generally the equation for the density  is mathematically given as

[tex]phi=\frac{m}{v}[/tex]

Where

v= 50 cm * 100 cm * 200 cm

v=1000000cm

v=10000m

Therefore

[tex]phi=\frac{m}{v}\\\\phi=\frac{8}{10000}[/tex]

phi=8e-4

For more information on density

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Answer:

A hypothesis predicts the value of a dependent variable given an independent variable:

If a person weighs 50 kg (independent variable) the weight hypothesis predicts that W = 50 * 9.8 = 490 N (the dependent variable)

So those three should be present in an investigation

Answer:

The half-life of a radioactive isotope is the time taken for half the unstable nuclei in a sample to decay.

An ampere (AM-pir), or amp

Answer:

The freezer compartment is at the top of a fridge because cool air sinks. (convection current)

Explanation:

________________________________

The metal ball lost energy while the putty ball gained energy.

Momentum is the product of mass and velocity of the body. We must note that momentum before collision is equal to momentum after collision.

1) Kinetic energy before collision = 1/2mv^2 = 0.5 * 6 * 4 = 12 J

2) kinetic energy after collision = 0.5 * 6 *  2= 6 J

3) Kinetic energy of putty ball = 0.5 * 6 *  2= 6 J

4) Energy lost by the metal ball = 12 J -  6 J = 6 J

5) Energy gained by the putty ball = 6 J - 0J = 6 J

6) The rest of the energy was converted to heat after the collision.

Learn more about kinetic energy: https://brainly.com/question/999862

Answer:

Yes, it can be destroyed.The total amount of matter (atoms) before and after a chemical reaction (change), remains the same.

Explanation:

hope this helps