All categories

3 years ago

What would happen if the sun suddenly became a black hole without changing its mass?

Physics

1 answer:

Sloan [31]3 years ago

4 0

Answer:

It would shrink to a radius of 2.95 km

Explanation:

In order to be a black hole, the Sun must shrink so that its radius becomes equal to its Schwarzschild radius:

$r=\frac{2GM}{c^2}$

where

G is the gravitational constant

$M=1.99\cdot 10^{30} kg$ is the mass of the Sun

c is the speed of light

Substituting into the equation, we find

$r=\frac{2(6.67\cdot 10^{-11}m^3 kg^{-1} s^{-2})(1.99\cdot 10^{30} kg)}{(3\cdot 10^8 m/s)^2}=2950 m=2.95 km$

So, the Sun should shrink to a radius of 2.95 km.

You might be interested in

The basic barometer can be used as an altitude-measuring device in airplanes. The ground control reports a barometric reading of

kipiarov [429]

Answer:

Δh_air=714m

Explanation:

Given data

$P_{1}=753mmHg\\P_{2}=690mmHg\\ p_{air}=1.2kg/m^{3}\\ g=9.8m/s^{2}$

Solution

ΔP=P₁-P₂

=(ΔhHg)×pHg×g

=(Δh_air)× p_air ×g

Then

Δh_air=(pHg+ΔhHg)÷p_air

$=\frac{13600*(753-690)*10^{-3} }{1.2}\\ =714m$

Δh_air=714m

7 0

3 years ago

Early black-and-white television sets used an electron beam to draw a picture on the screen. The electrons in the beam were acce

lutik1710 [3]

Answer:

speed of electrons = 3.25 × $10^{7}$ m/s

acceleration in term g is 3.9 × $10^{17}$ g.

radius of circular orbit is 2.76 × $10^{-4}$ m

Explanation:

given data

voltage = 3 kV

magnetic field = 0.66 T

solution

law of conservation of energy

PE = KE

qV = 0.5 × m × v²

v = $\sqrt{\frac{2qV}{m}}$

v = $\sqrt{\frac{2\times 1.6 \times 10^{-19}\times 3}{9.1\times 10^{-31}}$

v = 3.25 × $10^{7}$ m/s

and

magnetic force on particle movie in magnetic field

F = Bqv

ma = Bqv

a = $\frac{Bqv}{m}$

a = $\frac{0.67\times 1.6\times 10^{-19}\times 3.25\times 10^7}{9.1\times 10^{-31}}$

a = 3.82 × $10^{18}$ m/s²

and acceleration in term g

a = $\frac{3.82\times 10^{18}}{9.81}$

a = 3.9 × $10^{17}$ g

acceleration in term g is 3.9 × $10^{17}$ g.

and

electron moving in circular orbit has centripetal force

F = $\frac{mv^2}{r}$

Bqv = $\frac{mv^2}{r}$

r = $\frac{mv}{Bq}$

r = $\frac{9.1\times 10^{-31}\times 3.25\times 10^7}{0.67\times 1.6\times 10^{-19}}$

r = 2.76 × $10^{-4}$ m

radius of circular orbit is 2.76 × $10^{-4}$ m

8 0

4 years ago

A 12.0-g plastic ball is dropped from a height of 2.50 m. Just as it strikes the floor, it is moving at a speed of 3.20 m/s. How

nalin [4]

Answer:

0·233 J

Explanation:

Given

Mass of the ball = 0·012 kg

Initially the ball is at a height of 2·5 m

As initially the ball is dropped, it's initial velocity will be equal to 0

Therefore initially it has zero kinetic energy and has only potential energy

∴ Initially total mechanical energy of the ball = potential energy of the ball

Initial potential energy of the ball = m × g × h

where

m is the mass of the ball

g is the acceleration due to gravity

h is the height of the ball

∴ Potential energy = 0·012 × 9·8 × 2·5 = 0·294 J

Velocity of the ball after striking the floor = 3·2 m/s

After striking the floor, the total mechanical energy = kinetic energy just after striking the floor

Kinetic energy = 0·5 × m × v²

where m is the mass of the ball

v is the velocity of the ball

∴ Kinetic energy of the ball = 0·5 × 0·012 × 3·2² = 0·061 J

Mechanical energy that is lost = 0·294 - 0·061 = 0·233 J

∴ Mechanical energy that the ball lost during its fall = 0·233 J

6 0

3 years ago

The table represents the speed of a car in a northern direction over several seconds. A 2-column table with 5 rows. The first co

Oksanka [162]

Answer:

Column 1 should be titled “Time,” and Column 2 should be titled

“Velocity.” ⇒ 1st answer

Explanation:

* Lets revise some definitions of graphs

A velocity-time graph represents the speed and direction an object

travels over a period of time.

Velocity-time graph is called speed-time graph.

The vertical axis of a velocity-time graph represents the velocity of the

object and horizontal axis represents the time from the initial position

In an acceleration time graph y-axis represents the acceleration, and

x-axis represents the time

The table represents the speed of a car in a northern direction over

several seconds

That means the data in the table represent the velocity of the car in a

certain time

Time (s) Velocity (m/s)

0 5

2 10

4 15

6 20

8 25

10 30

Column 1 would be on the x-axis

x-axis represents the time

Column 2 would be on the y-axis

y-axis represents the velocity

Column 1 should be titled “Time,” and Column 2 should be titled

“Velocity.”

3 0

4 years ago

Read 2 more answers

Name the particle in the nucleus of an atom that gives the nucleus a positive charge

Crazy boy [7]

The answer is d...............

8 0

3 years ago

Read 2 more answers