How Do Seatbelts Work?
Seatbelts are very important safety devices that have saved many lives. Early seatbelts, created in the 1900s, were uncomfortable and could cause injuries because they only went across the lap. People were not interested in using them for many years. In the 1950s, a Swedish engineer named Nils Bohlin developed the three-point seatbelt, which is the design we use today. This design spreads the force of a crash across the shoulders and hips, making it much safer. Volvo released this design for free so everyone could use it. Modern seatbelts have clever parts that lock the belt during a sudden stop and even pull you tighter into the seat before a crash. They also have features to reduce injuries. Even though seatbelts are very effective, it took a long time for laws to make people wear them. Seatbelts save thousands of lives every year, so it's important to always wear them.
Key Vocabulary
To sit or fall heavily and limply, often indicating a relaxed or unconscious posture.
Examples:
- After a long day of work, he tends to slump onto the couch as soon as he gets home.
- The tired student would often slump in their chair during the afternoon lecture.
- She tried to prevent herself from slumping forward when the train suddenly braked.
People with whom one works, especially in a professional or office setting.
Examples:
- My coworkers and I often grab lunch together on Fridays.
- She organized a surprise birthday party for one of her favorite coworkers.
- Effective communication is key to a positive relationship with your coworkers.
To crush or compress something, especially paper or fabric, into a wrinkled or folded mass; to collapse or break down completely.
Examples:
- He watched the old car crumple under the impact of the collision.
- She was so frustrated that she wanted to crumple the report and throw it away.
- The delicate flower petals began to crumple after being exposed to the harsh sun.
To bring into effective action; to set up or position for use.
Examples:
- The emergency services were quick to deploy their resources at the scene of the accident.
- The company plans to deploy new software updates to all its systems next month.
- Before starting the mission, the team had to deploy their specialized equipment.
To cause a machine or device to operate or move.
Examples:
- The sensor is designed to actuate the alarm system when it detects any motion.
- A small lever can be used to actuate the release mechanism.
- The remote control actuates the drone's propellers, allowing it to take flight.
A mechanism that allows movement in one direction only, typically by means of a pawl engaging with a toothed wheel.
Examples:
- He used a wrench with a ratchet mechanism to tighten the bolt securely.
- The car jack uses a ratchet system to lift the vehicle incrementally.
- The sound of the ratchet clicking indicated that the security lock was engaged.
Reduces speed; slows down.
Examples:
- As the train approaches the station, it gradually decelerates.
- The car decelerates smoothly when the driver applies the brakes.
- When a spacecraft enters Earth's atmosphere, it rapidly decelerates due to atmospheric drag.
The action of twisting or the state of being twisted, especially of one end of an object relative to the other.
Examples:
- The bridge was designed to withstand significant torsion from strong winds.
- Engineers calculated the amount of torsion a metal rod could endure before breaking.
- The spring experienced considerable torsion as it was wound tightly.
Catches fire or causes to catch fire.
Examples:
- A single spark can ignite the dry kindling.
- The chemical reaction ignites when the two substances are mixed.
- The engine ignites the fuel-air mixture to produce power.
A cylindrical device on which film, magnetic tape, thread, or other flexible materials can be wound.
Examples:
- The fishing line was neatly wound around the spool of the reel.
- She carefully placed the thread spool onto the sewing machine.
- The old projector used a large spool to hold the film.
A strong negative reaction by a large number of people, especially to a social or political development.
Examples:
- The company faced significant public backlash after announcing its controversial new policy.
- There was widespread backlash against the proposed tax increase.
- The celebrity's comments sparked a huge backlash on social media.
Loose; not taut or tense.
Examples:
- Make sure there is no slack in the rope before you begin to climb.
- The tent ropes became slack after the rain, so we had to tighten them.
- He adjusted the guitar strings to remove any slack and improve the sound.
To gradually lessen or reduce; to recede.
Examples:
- His enthusiasm for the project began to ebb after several setbacks.
- The crowd's excitement started to ebb as the concert drew to a close.
- The tide will ebb, revealing more of the sandy beach.
Relating to the lower part of the back, between the ribs and the pelvis.
Examples:
- Many office chairs offer adjustable lumbar support to promote good posture.
- He experienced a sharp pain in his lumbar region after lifting heavy boxes.
- The physiotherapist recommended exercises to strengthen the patient's lumbar muscles.
A weight hung from a fixed point so that it can swing freely backward and forward, especially a rod with a weight at the end that regulates the mechanism of a clock.
Examples:
- The grandfather clock had a long, graceful pendulum swinging steadily.
- He observed the precise movement of the pendulum in the science experiment.
- The debate often swings like a pendulum between two opposing viewpoints.
A strip of flexible material used for fastening, holding together, or carrying.
Examples:
- She adjusted the strap of her backpack for a more comfortable fit.
- The camera had a durable strap that allowed him to carry it securely around his neck.
- He used a leather strap to tie the luggage to the roof rack.
The state of being no longer needed or useful; specifically, the inclusion of extra components or systems in a design to ensure continued operation in case of failure.
Examples:
- The spacecraft's design included multiple layers of redundancy for critical systems.
- To ensure data safety, the server has built-in redundancy with mirrored drives.
- The company implemented a redundancy plan to minimize disruption during power outages.
A strap or harness designed to secure a person in a seat, especially in a vehicle or aircraft, to prevent injury in a collision or sudden stop.
Examples:
- Always fasten your seatbelt before the car starts moving.
- The pilot reminded all passengers to keep their seatbelts fastened during turbulence.
- Wearing a seatbelt significantly increases safety for drivers and passengers.
Taken or acquired in an unfair or illicit way, often referring to employees being hired away from a competitor.
Examples:
- The rival company successfully poached several key engineers from our research department.
- He was poached by a larger firm after his impressive work on the recent project.
- The restaurant chain has a reputation for poaching talented chefs from smaller establishments.
A disk or short cylinder fitting closely within a cylindrical vessel, moving to and fro under fluid pressure or serving to compress or displace fluid.
Examples:
- The engine's piston moves up and down rapidly to generate power.
- The hydraulic system uses a piston to lift heavy loads.
- As the gas expands, it pushes the piston, driving the machinery.