1.
What is the boundary of the region from which no escape is possible called?
Correct Answer
A. Event horizon
Explanation
The boundary of the region from which no escape is possible is called the event horizon. This is the point of no return for anything that enters the gravitational pull of a black hole. Once an object crosses the event horizon, it is trapped within the black hole's intense gravitational field and cannot escape. The event horizon is a defining feature of black holes and plays a crucial role in understanding their behavior and properties.
2.
What century saw the gravitational field responsible for black hole explained?
Correct Answer
A. 12th century
3.
Why is the black hole regarded as a black body?
Correct Answer
A. It absorbs light
Explanation
A black hole is regarded as a black body because it absorbs light. Unlike other objects in space, a black hole has such a strong gravitational pull that nothing, including light, can escape from it. As a result, the black hole appears black and does not reflect or emit any light. This property of absorbing all light is why it is referred to as a black body.
4.
When was the first modern solution of general relativity for the black hole found?
Correct Answer
A. 1917
Explanation
In 1917, the first modern solution of general relativity for the black hole was found. This breakthrough in understanding the nature of black holes was a significant development in the field of astrophysics. It provided a mathematical framework to describe the behavior and properties of black holes, leading to further advancements in the study of these enigmatic astronomical objects.
5.
Who found a modern solution of general relativity for the black hole problem?
Correct Answer
D. Karl Schwarzchild
Explanation
Karl Schwarzschild is credited with finding a modern solution to the black hole problem in general relativity. His solution, known as the Schwarzschild metric, describes the geometry of spacetime around a non-rotating and non-charged black hole. This solution provided a mathematical framework for understanding the properties and behavior of black holes, including the existence of an event horizon and the singularity at the center. Schwarzschild's work laid the foundation for further research and exploration of black holes in the field of astrophysics.
6.
Who interpreted the solution for the black hole problem?
Correct Answer
A. Eric Walter
7.
When was the solutionof the black hole problem made?
Correct Answer
A. 1928
Explanation
The solution to the black hole problem was made in 1928.
8.
When was neutron stars discovered?
Correct Answer
A. 1961
Explanation
Neutron stars were discovered in 1961. This discovery was made by a graduate student named Jocelyn Bell Burnell and her advisor Antony Hewish. They observed regular radio pulses coming from a specific location in the sky, which they initially thought might be signals from extraterrestrial intelligence. However, further analysis revealed that these signals were actually coming from a rapidly spinning neutron star, which became known as a pulsar. This groundbreaking discovery revolutionized our understanding of stellar remnants and earned Hewish the Nobel Prize in Physics in 1974.
9.
Who discovered the neutron stars?
Correct Answer
A. Jocelyn Burnell
Explanation
Jocelyn Burnell is credited with the discovery of neutron stars. In 1967, while working as a graduate student, she detected regular radio pulses coming from a region of the sky. These pulses were later identified as coming from a rapidly rotating neutron star, known as a pulsar. This groundbreaking discovery revolutionized our understanding of stellar remnants and earned Burnell significant recognition in the field of astrophysics.
10.
When was the first time a direct image of the black hole published?
Correct Answer
A. 10 April 2019
Explanation
The first direct image of a black hole was published on 10 April 2019. This breakthrough was made possible by the Event Horizon Telescope (EHT), which is a network of telescopes around the globe that work together to create a virtual telescope the size of the Earth. The image captured the supermassive black hole at the center of the galaxy M87, providing visual evidence of the existence of these mysterious cosmic objects.