Sigmund Freud revolutionized our understanding of dreams by proposing that they are a window into the unconscious mind. According to Freud, dreams are not mere stories our minds create while we sleep but are profoundly meaningful narratives about our hidden desires and fears. He introduced two key concepts: manifest content and latent content. The manifest content is the actual content and imagery of the dream — what we remember when we wake up. The latent content, however, represents the...

According to Newton’s second law of motion, the rate of change of the momentum of an object is the net external force acting on it. The total change in momentum between two timepoints thus depends on both the external force acting on it and the time over which it acts. Describing this mathematically, the total change of an object’s motion is proportional to the force vector and the time over which it is applied. This product is called impulse.
Additionally, it can be shown that the...

Amnesia is a condition marked by long-term memory loss, which impairs the ability to recall past events or create new memories.
The severity and duration of memory loss vary depending on the type and underlying cause. Amnesia is classified into two main types: retrograde and anterograde.
Retrograde amnesia is marked by the loss of memories formed before the onset of the condition. Patients may recall distant past events but often forget those occurring shortly before the incident.
Anterograde...

Lucid dreaming is a unique state of consciousness where an individual realizes they are dreaming while still in the dream. This awareness allows them to manipulate their dream environment consciously. Researchers like Stephen LaBerge have significantly contributed to the understanding of lucid dreams, highlighting that during these dreams, certain areas of the brain, such as the prefrontal cortex, that involve self-awareness and thought evaluation show increased activity.
Studies have shown...

The human heart is a complex organ made up of four chambers: the right and left atria and the right and left ventricles. These internal chambers are separated by partitions known as the interatrial and interventricular septa. The exterior of the heart features a groove known as the coronary sulcus that demarcates the atria from the ventricles, while the anterior and posterior interventricular sulci distinguish between the two ventricles.
Deoxygenated blood from the body is received in the right...

Mechanical engineering involves the study of motion, energy, and force, and is concerned with designing, manufacturing, and maintaining mechanical systems. One important concept in this field is the couple moment, produced by two equal and opposite forces acting at two points in a rigid body separated by a certain distance.
When the rigid body undergoes a differential displacement due to a couple, its motion can be divided into two parts: equal translation of the two points to their final...