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
timofeeve [1]
3 years ago
14

An astronomy student, for her PhD, really needs to estimate the age of a cluster of stars. Which of the following would be part

of the process she would follow?
A. plot an H-R diagram for the stars in the cluster
B. count the number of M type stars in the cluster
C. measure the Doppler shift of a number of the stars in the cluster
D. search for planets like Jupiter around the stars in the center of the cluster
E. search for x-rays coming from the center of the cluster
Physics
1 answer:
LiRa [457]3 years ago
4 0

Answer:

A. plot an H-R diagram for the stars in the cluster.

Explanation:

A star cluster can be defined as a constellation of stars, due to gravitational force, which has the same origin.

The astronomy student would have to plot an H-R diagram for the stars in the cluster and determine the age of the cluster by observing the turn-off point. The turn-off is majorly as a result of gradual depletion of the source of energy of the star. Thus, it projects off the constellation.

You might be interested in
The bodies of many cars are designed to compress or crumple during an accident. Why are cars built with a crumple zone?
Kryger [21]
By collapsing and crumpling, the force and energy is absorbed by the crumple zone and it is not transferred to the passengers inside. This is a safety feature for the passengers.
8 0
3 years ago
A nova occurs when
eimsori [14]

C. hydrogen accreted onto a white dwarf from a close companion rapidly fuses to helium, releasing a large amount of energy.

The accreted material, composed mainly of hydrogen, is compacted on the surface of the white dwarf due to the intense gravitational force on that place. As material accumulates, The white dwarf becomes increasingly hot, until it reaches the critical temperature for ignition of nuclear fusion.

5 0
3 years ago
Three cars (car F, car G, and car H) are moving with the same speed and slam on their brakes. The most massive car is car F, and
Crazy boy [7]

To solve this problem it is necessary to apply the concepts related to Normal Force, frictional force, kinematic equations of motion and Newton's second law.

From the kinematic equations of motion we know that the relationship of acceleration, velocity and distance is given by

v_f^2=v_i^2+2ax

Where,

v_f = Final velocity

v_i = Initial Velocity

a = Acceleration

x = Displacement

Acceleration can be expressed in terms of the drag coefficient by means of

F_f = \mu_k (mg)  \rightarrowFrictional Force

F = ma \rightarrow Force by Newton's second Law

Where,

m = mass

a= acceleration

\mu_k = Kinetic frictional coefficient

g = Gravity

Equating both equation we have that

F_f = F

\mu_k mg=ma

a = \mu_k g

Therefore,

v_f^2=v_i^2+2ax

0=v_i^2+2(\mu_k g)x

Re-arrange to find x,

x = \frac{v_i^2}{2(-\mu_k g)}

The distance traveled by the car depends on the coefficient of kinetic friction, acceleration due to gravity and initial velocity, therefore the three cars will stop at the same distance.

3 0
3 years ago
Rahul sits in a chair reading a book. Which force is equal to the force Rahul exerts on Earth?
Mademuasel [1]
The first opiton is the answer A)<span>Rahul’s weight
</span>
8 0
3 years ago
Read 2 more answers
Three heavy rods are all made of the same uniform material. These rods have lengths 3 m, 4 m, and 5 m, and compose the sides of
Sonbull [250]

Answer:

[ 2.67 , 1 ] m

Explanation:

Given:-

- The side lengths of the rods are as follows:

                             a = 4 m , b = 4 m , c = 5 m

                             a = Base , b = Perpendicular , c = Hypotenuse

- All rods are made of same material with uniform density. With  

Find:-

Find the coordinates of the center of mass of the triangle.

Solution:-

- The center of mass of any triangle is at the intersection of its medians.

- So let’s say we have a triangle with vertices at points (0,0) , (a,0) , and (0,b).

  • Median from (0,0) to midpoint (a/2,b/2) of opposite side has equation:

                                       bx−ay=0

  • Median from (a,0) to midpoint (0,b/2) of opposite side has equation:

                                      bx+2ay=ab

  • Median from (0,b) to midpoint (a/2,0) of opposite side has equation:

                                     2bx+ay=ab

  • Solve all three equations simultaneously:

                                     bx−ay=0  , bx = ay

                                     ay + 2ay = ab , 3ay = ab , y = b/3

                                     bx = b/3

                                     x = a / 3

  • So the distance from the median to each leg of the triangle is 1/3 length of other leg.

- So the coordinates of the centroid for right angle triangle would be:

                                   [ 2a/3 , b/3 ]

                                   [ 2.67 , 1 ] m

                                                         

                                 

3 0
3 years ago
Other questions:
  • A rocket rises vertically, from rest, with an acceleration of 3.2 m/s^2 until it runs out of fuel at an altitude of 725 m . Afte
    14·1 answer
  • In a transverse wave, ____________________ is measured from crest to crest or from trough to trough.
    10·2 answers
  • Samuel is running in a parks nature trail.at first checkpoint he ran 925 m in 10 minutes.at second checkpoint he slowed down and
    10·1 answer
  • Coal is considered to be a non-renewable energy source. Which of the following statements is correct? a. Coal is a scarce resour
    14·1 answer
  • The states that mas cannot be created or destroyed
    15·2 answers
  • A)If the rms value of the electric field in an electromagnetic wave is doubled, by what factor does the rms value of the magneti
    9·1 answer
  • Is a step in the scientific method. The step that follows this step involves forming
    14·1 answer
  • Pulling a rubber band back and then letting it fly across the room is an example of
    13·1 answer
  • Many people who have contracted a disease called chicken pox were told by their doctors that they would never have this
    5·1 answer
  • The noise from a power mower was measured at 104 dB. The noise level at a rock concert was measured at 121 dB. Find the ratio of
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!