1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
saul85 [17]
3 years ago
11

A typical stellar spectrum (a plot of intensity versus wavelength) includes a number of deep indentations in which the intensity

abruptly falls and then rises. These deep indentations are called ____ lines.
Physics
1 answer:
belka [17]3 years ago
7 0

Answer:

They are called absorption lines

Explanation:

Absorption lines are defined as dark lines or lines having reduced intensity, on an ongoing spectrum. A typical example is noticed in the spectra of stars, where gas existing in the outer layers of the star absorbs some of the light from the underlying thermal blackbody spectrum.

You might be interested in
An empty train car of mass 2.0 x 10^4 kg coasts along at 10 m/s. A 3000-kg boulder is suddenly dropped vertically into the car.
Zepler [3.9K]

Answer:8.69 m/s

Explanation:

Given

mass of Empty train m=2\times 10^4 kg

velocity of car v=10 m/s

mass of Boulder M=3000 kg

Since no External force is acting therefore conserving Momentum

Train and boulder moves with same velocity after collision

m v=(M+m)v'

2\times 10^4\times 10=(2\times 10^4+3000)v'

v'=\frac{20,000\times 10}{23000}

v'=8.69 m/s

8 0
3 years ago
I have three questions. John has to hit a bottle with a ball to win a prize. He throws a 0.4 kg ball with a velocity of 18 m/s.
AfilCa [17]

1. 5.5 m/s

We can solve the problem by applying the law of conservation of momentum. The total momentum before the collision must be equal to the total momentum after the collision, so we have:

m_1 u_1 + m_2 u_2 = m_1 v_1 + m_2 v_2

where

m1 = 0.4 kg is the mass of the ball

u1 = 18 m/s is the initial velocity of the ball

m2 = 0.2 kg is the mass of the bottle

u2 = 0 is the initial velocity of the bottle (which is initially at rest)

v1 = ? is the final velocity of the ball

v2 = 25 m/s is the final velocity of the bottle

Substituting and re-arranging the equation, we can find the final velocity of the ball:

v_1 = \frac{m_1 u_1 - m_2 v_2}{m_1}=\frac{(0.4 kg)(18m/s)-(0.2 kg)(25 m/s)}{0.4 kg}=5.5 m/s


2. 22.2 m/s

We can solve the problem again by using the law of conservation of momentum; the only difference in this case is that the bullet and the block, after the collision, travel together at the same speed v. So we can write:

m_1 u_1 + m_2 u_2 = (m_1 +m_2) v

where

m1 = 0.04 kg is the mass of the bullet

u1 = 300 m/s is the initial velocity of the bullet

m2 = 0.5 kg is the mass of the block

u2 = 0 is the initial velocity of the block (which is initially at rest)

v = ? is the final velocity of the bullet+block, which stick and travel together

Substituting and re-arranging the equation, we can find the final velocity of bullet+block:

\frac{m_1 u_1}{m_1 +m_2}=\frac{(0.04 kg)(300 m/s)}{0.04 kg+0.5 kg}=22.2 m/s


3. 6560 N

The impulse exerted on the ball is equal to its change in momentum:

I=\Delta p (1)

The impulse can be rewritten as product between force and time of collision:

I=F \Delta t

while the change in momentum of the ball is equal to the product between its mass and the change in velocity:

\Delta p = m\Delta v = m(v_f -v_i)

So, eq.(1) becomes

F \Delta t = m(v_f -v_i)

where:

F = ? is the unknown force

\Delta t = 0.002 s is the duration of the impact

m = 0.16 kg is the mass of the ball

v_f = 44 m/s is the final velocity of the ball

v_i = -38 m/s is its initial velocity (we must add a negative sign, since it is in opposite direction to the final velocity)

So, by using the equation, we can find the force:

F=\frac{m (v_f -v_i)}{\Delta t}=\frac{(0.16 kg)(44 m/s-(-38 m/s))}{0.002 s}=6560 N

7 0
3 years ago
Calculate the density of water at 22.3 degrees celsius
lys-0071 [83]
The density of water at 22.3 degrees Celsius is 72.14 degrees .
6 0
3 years ago
Define investigation to show its scientific meaning.
Murrr4er [49]

Answer:

the action of investigating something or someone; formal or systematic examination or research.

Explanation:

This definition is provided by Oxford Languages

7 0
3 years ago
I need some help with my science homework about energy, work, and power. It would be greatly appreciated :)
fgiga [73]

Answer:

1. B

Explanation:

Work = Force × Distance

Work = 4N × 1.5M

5 0
4 years ago
Other questions:
  • A ray of light passes from air into carbon disulfide (n = 1.63) at an angle of 28.0 degrees to the normal. what is the refracted
    13·1 answer
  • A duck floating on a lake oscillates up and down
    11·1 answer
  • A child and sled with a combined mass of 50.2 kg slide down a frictionless hill that is 8.38 m high. If the sled starts from res
    9·1 answer
  • The waters of a lake will be most layered in which season
    5·1 answer
  • NEVERMIN I've got it. :D
    15·1 answer
  • Can someone help me please step by step
    10·1 answer
  • What is the magnitude of the instantaneous velocity (speed) of a freely falling object 25 s after it is released from a position
    8·1 answer
  • A horizontal force of 200 N is applied to move a 55 kg television set across a 10 m level surface. What is the work done by the
    8·1 answer
  • 32. Increasing the amplitude of a sound wave produces a
    12·1 answer
  • What is a force that opposes motion between two surfaces that are in contact?
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!