All categories

3 years ago

What is an event horizon? Does our Sun have an event horizon around it?

Physics

1 answer:

STatiana [176]3 years ago

6 0

Answer:

The event horizon of a black hole can be thought of either as the place around the black hole where the speed you need to escape becomes greater than the speed of light or as the place where the warping of spacetime around a collapsed star becomes so great that all straight lines pointing outward actually become curved paths bringing you back in. Only black holes have event horizons, so our Sun, which is a star in happy main-sequence equilibrium, cannot have one.

You might be interested in

A flywheel in the form of a uniformly thick disk of radius 1.33 m1.33 m has a mass of 70.6 kg70.6 kg and spins counterclockwise

ladessa [460]

Answer:

The constant torque required to stop the disk is 8.6 N-m in clockwise direction .

Explanation:

Let counterclockwise be positive direction and clockwise be negative direction .

Given

Radius of disk , r = 1.33 m

Mass of disc , m = 70.6 kg

Initial angular velocity , $\omega_i =217 rpm$

Final angular velocity , $\omega_f =0\, rpm$

Time taken to stop , t = 2.75 min

Let $\alpha$ be the angular acceleration

We know

$\omega _f=\omega _i+\alpha t$

=> $0=217+2.75\alpha =>\alpha = -78.9\frac{rev}{min^{2}}$

=> $\alpha =-\frac{78.9\times 2\pi}{60\times 60}\frac{rad}{s^{2}}=-0.138 \frac{rad}{s^{2}}$

Torque required to stop is given by

$\tau =I\alpha$

where moment of inertia , $I=\frac{mr^{2}}{2}=\frac{70.6\times 1.33^{2}}{2}kg.m^{2}=62.5 kg.m^{2}$

=> $\therefore \tau =-0.138\times 62.5\, N.m=-8.6\, N.m$

Thus the constant torque required to stop the disk is 8.6 N-m in clockwise direction .

3 0

2 years ago

The equation most often associated with Newton's Second Law of Motion is<br> Answer here

zloy xaker [14]

Answer: F=ma

Explanation:

7 0

2 years ago

Read 2 more answers

Quando ocorre um eclipse total da lua?

MissTica

Um eclipse solar ocorre quando a lua fica entre a Terra e o sol, e a lua projeta uma sombra sobre a Terra. Um eclipse solar só pode ocorrer na fase da lua nova, quando a lua passa diretamente entre o sol e a Terra e suas sombras caem sobre a superfície da Terra.

3 0

2 years ago

What type of nuclear decay releases energy but not a particle?

statuscvo [17]

I believe gamma decay but i may be wrong

7 0

3 years ago

Read 2 more answers

a ball rolls along the floor with a constant velocity of 3 m/s. How far will it have gone after 234 seconds?

sergij07 [2.7K]

Answer:

The ball travel for 702m