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
romanna [79]
3 years ago
13

What does the term Hubble time mean in cosmology, and what is the current best calculation for the Hubble time?

Physics
1 answer:
balu736 [363]3 years ago
4 0

Hubble time in cosmology means the estimated age of the universe and the best calculation for it is T=1/H, where H is the Hubble constant
You might be interested in
An emf of 28.0 mV is induced in a 501 turn coil when the current is changing at a rate of 12.0 A/s. What is the magnetic flux th
dmitriy555 [2]

Answer:

Φ = 5.589×10⁻⁵  Wb

Explanation:

The inductance of a coil is given as

L = e/(di/dt) ..................... Equation 1

Where L = inductance of the coil, e = induced e.m.f, di/dt = rate of change of current in the coil.

Also,

The inductance of each turn of the coil when a magnetic field is step up in the coil  is

L = NΦ/i ................. Equation 2

Where N = number of turns, Φ = magnetic field, i = current.

equating equation 1 and equation 2

e/(di/dt) = NΦ/i

making Φ the subject of the equation,

Φ = (e×i)/N.(di/dt) .................. Equation 3

Given: e = 28.0 mV = 0.028 V, N = 501 turns, di/dt = 12.0 A/s, i = 4.00 a

Substitute into equation 3,

Φ = (0.028×4)/(12×501)

Φ = 0.112/2004

Φ = 5.589×10⁻⁵ Weber

Φ = 5.589×10⁻⁵ Wb

6 0
3 years ago
What shape is the graph produced by a force vs acceleration graph?
hammer [34]

The answer to the question<u> What shape is the graph produced by a force vs acceleration graph</u> is A. Linear

Since Force, F = ma where m = mass and a = acceleration. For constant mass, F ∝ a. That is, F is directly proportional to acceleration, a.

Since this is a linear relationship, the graph of force vs acceleration will be linear.

The answer to the question<u> What shape is the graph produced by a force vs acceleration graph</u> is A. Linear

Learn more about graphs here:

brainly.com/question/24322515

6 0
2 years ago
A subway train starts from rest at a station and accelerates at a rate of 1.68 m/s2 for 14.2 s. It runs at constant speed for 68
liubo4ka [24]

Answer:

total distance = 1868.478 m

Explanation:

given data

accelerate = 1.68 m/s²

time = 14.2 s

constant time = 68 s

speed = 3.70 m/s²

to find out

total distance

solution

we know train start at rest so final velocity will be after 14 .2 s is

velocity final = acceleration × time      ..............1

final velocity = 1.68 × 14.2

final velocity = 23.856 m/s²

and for stop train we need time that is

final velocity = u + at

23.856 = 0 + 3.70(t)

t = 6.44 s

and

distance = ut + 1/2 × at²     ...........2

here u is initial velocity and t is time for 14.2 sec

distance 1 = 0 + 1/2 × 1.68 (14.2)²

distance 1 = 169.37 m

and

distance for 68 sec

distance 2= final velocity × time

distance 2= 23.856 × 68

distance 2 = 1622.208 m

and

distance for 6.44 sec

distance 3 = ut + 1/2 × at²

distance 3 = 23.856(6.44) - 0.5 (3.70) (6.44)²

distance 3 = 76.90 m

so

total distance = distance 1 + distance 2 + distance 3

total distance = 169.37 + 1622.208 + 76.90

total distance = 1868.478 m

7 0
3 years ago
Read 2 more answers
a man is standing near the edge of a cliff 85 meters high. he throws a stone upward vertically with an intial velocity of 10 m/s
alex41 [277]

Answer:

h = 90.10 m

Explanation:

Given that,

A man is standing near the edge of a cliff 85 meters high, h₀ = 85 m

The initial speed of the stone, u = 10 m/s

The path followed by the projectile is given by :

h(t)=-4.9t^2+10t+85 ....(1)

For maximum height,

Put dh/dt = 0

So,

\dfrac{dh}{dt}=-9.8t+10=0\\\\t=\dfrac{10}{9.8}\\\\=1.02\ s

Put the value of t in equation (1).

h(t)=-4.9(1.02)^2+10(1.02)+85\\\\=90.10\ m

So, the maximum height of the stone is equal to 90.10 m.

5 0
3 years ago
Does a good insulator prevent energy from getting through it, or slow its passage
9966 [12]
A good heat insulator absorbs all, or almost all, of the heat energy
from any heat that flows through it.

A good electrical insulator absorbs all, or almost all, of the energy
from any electric current that flows through it.
8 0
3 years ago
Other questions:
  • How much heat is released when 432 g of water cools down from 71'c to 18'c?
    13·1 answer
  • a parallel circuit has two 8.0 ohm resistors and a power source of 9.0 volts. Of a 12.5 ohm resistor is added to the circuit in
    8·2 answers
  • Why should a tennis player "swing through" when hitting a tennis ball?​
    10·1 answer
  • Describe the relationship of attractive forces between molecules
    15·1 answer
  • Please Help! 30 points! ASAP PLZ :)
    8·2 answers
  • Ocean breezes are due to which method of heat transfer?
    10·2 answers
  • Who are people that you can go to for help name three?
    9·2 answers
  • A string is stretched to a length of 361 cm and both ends are fixed. If the density of the string is 0.039 g/cm, and its tension
    12·1 answer
  • HELP PLS! :/
    6·1 answer
  • Do some research on digital vs. analog recording, and decide which you think gives the most accurate and best quality sound. Sta
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!