A magnetic resonance imaging (MRI), is a device used in radiology to form pictures of the anatomy and the physiological process of the body. The patient is placed on a moveable bed that is inserted into the circular magnet, which the tube shaped MRI scanner is surrounded by. The water molecules (H2O) in a human body which contain hydrogen nuclei (protons), are like tiny magnets and are highly sensitive to magnetic fields. The machine works by aligning these protons in the patient’s body. Short bursts of radio waves are sent to the certain areas of the body, which move the protons out of alignment. When the radio waves are turned off, the protons realign, which sends signals that are picked up by receivers. These signals provide information about the exact location of the protons in the body and help to distinguish between the various types of tissue in the body (the protons in different types of tissue realign at different speeds and produce distinct signals). MRI scanners are safe and harmless, they do not use ionizing radiation, which reduces the exposure of potential harm to the patient. While most internal scanning methods like CAT scans and X-Rays use radiation, MRI’s use magnetic fields. The use of MRI could also  potentially decrease the number of diagnostic procedures a patient needs to undergo. But, due to the extremely strong magnets used in the MRI scanner, metal is prohibited anywhere near the scanner. This means that patients with metal fragments inside their body cannot undergo an MRI. Also people with pacemakers, artificial joints, dental fillings, braces, and so on, are unable to take MRI scans. In some cases, people with tattoos have difficulties with proceeding an MRI scan, due to traces of metal in the tattoo which  can cause discomfort to the tattoo and surrounding skin. Another downside of MRI scans is that they are very expensive, they usually range from about 700-1000 dollars depending on the type of scan needed. Which can be a problem for many people who can’t afford it.Magnetic levitation (Maglev) trains are a system of train transportation that uses magnets to move a train. Two types of magnets, one used to repel and push the train up off the track (levitation), and another set to move the ‘floating train’ ahead at great speed, with no friction. These trains are quieter and smoother than conventional trains, since there are really no moving parts, because the train travels along a guide way of magnets which control the trains stability and speed. Maglev trains can also accelerate and decelerate much faster than conventional trains, the only problem is the safety and comfort of the passengers. The percentage of the overall energy consumption of this system is not very high. Unlike land transport which has to overcome drag, making them more energy intense at higher speeds and taking up the most energy. Although it is very costly to construct a maglev train system (need their own separate tracks than normal trains and railroad tracks cost more) they are cheaper to manufacture and maintain.

Author