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3 years ago

How do scientists look for black holes in the sky

2 answers:

6 0

To find black holes in space, scientists use telescopes to study visible light, X-rays, and radio waves. When gas orbits a black hole, it gets very hot and starts emitting X-rays and radio waves. Through special telescopes, the area surrounding the black hole looks really bright.

pentagon [3]3 years ago

5 0

Scientists look through special telescopes and the area surrounding the black hole is suppose to look really bright.

You might be interested in

Why are airplanes filled with pressurized air and oxygen

zimovet [89]

Answer:

Airplane cabins are pressurized because as the airplane climbs higher in altitude, the air becomes very thin, this pressurization ensures that there is still enough breathable oxygen in the cabin to prevent everyone from suffering the effects of hypoxia and passing out.

plz give brainlist :'D

7 0

2 years ago

A car traveling at 50 m/s uniformly accelerates to 60 m/s over an 58 second interval. What is the displacement?

yawa3891 [41]

Explanation:

here u = 50m/s

v = 60m/s

t = 58 s

then a = (60-50)/58 m/s2

= 0.17m/s2

now s= ut+1/2at2

so , 50×58+0.5×0.17×(58)^2 m

= 3185.94 m

= 3.18 km

6 0

2 years ago

Read 2 more answers

A 20-kg block is held at rest on the inclined slope by a peg. A 2-kg pendulum starts at rest in a horizontal position when it is

gregori [183]

Complete Question

The diagram of this question is shown on the first uploaded image

Answer:

The distance the block slides before stopping is $d = 0.313 \ m$

Explanation:

The free body diagram for the diagram in the question is shown

From the diagram the angle is $\theta = 25 ^o$

$sin \theta = \frac{h}{d}$

Where $h = h_b - h_a$

So $d sin \theta = h_b - h_a$

From the question we are told that

The mass of the block is $m = 20 \ kg$

The mass of the pendulum is $m_p = 2 \ kg$

The velocity of the pendulum at the bottom of swing is $v_p = 15 m/s$

The coefficient of restitution is $e =0.7$

The coefficient of kinetic friction is $\mu _k = 0.5$

The velocity of the block after the impact is mathematically represented as

$v_2 f = \frac{m_b - em_p}{m_b + m_p} * v_2 i + \frac{[1 + e] m_1}{m_1 + m_2 } v_p$

Where $v_2 i$ is the velocity of the block before collision which is 0

$= \frac{20 - (0.7 * 2)}{(2 + 20)} * 0 + \frac{(1 + 0.7) * 2 }{2 + 20} * 15$

Substituting value

$v_2 f = 2.310\ m/s$

According to conservation of energy principle

The energy at point a = energy at point b

So $PE_A + KE _A = PE_B + KE_B + E_F$

Where

$PE_A$ is the potential energy at A which is mathematically represented as

$PE_A = m_b gh_a$ = 0 at the bottom

$KE _A$ is the kinetic energy at A which is mathematically represented as

$K_A = \frac{1}{2} m_b * v_2f^2$

$PE_B$ is the potential energy at B which is mathematically represented as

$PE_B = m_b gh$

From the diagram $h = h_b -h_a$

$PE_B = m_b g(h_b - h_a)$

$KE _B$ is the kinetic energy at B which is 0 (at the top )

Where is $E_F$ is the workdone against velocity which from the diagram is

$\mu_k m_b g cos 25 *d$

$\frac{1}{2} m_b v_2 f^2 = m_b g h_b + \mu_k m_b g cos \25 * d$

Substituting values

$\frac{1}{2} * 20 * 2.310^2 = 20 * 9.8 * d sin(25) + 0.5* 20 * 9.8 * cos 25 * d$

$d = 0.313 \ m$

6 0

3 years ago

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff ideal sprin

shepuryov [24]

Answer:

The magnitude of force must you apply to hold the platform in this position = 888.89 N

Explanation:

Given that :

Workdone (W) = 80.0 J

length x = 0.180 m

The equation for this work done by the spring is expressed as:

$W = \frac{1}{2}k_{eq}x^2$

Making the spring constant $k_{eq}$ the subject of the formula; we have:

$k_{eq} = \frac{2W}{x^2}$

Substituting our given values, we have:

$k_{eq} = \frac{2*80}{0.180^2}$

$k_{eq} = 4938.27 \ N.m^{-1}$

The magnitude of the force that must be apply to the hold platform in this position is given by the formula :

$F = k_{eq}x$

$F = 4938.27*0.180$

F = 888.89 N

6 0

3 years ago

An airplane flies with a constant speed of 560 miles per hour. How far can it travel in 1 1/2 hours?

Alik [6]

You would multiply the speed by the time. So the answer would be 840 miles.

5 0

2 years ago