THINKING TIME AND CAR CRASH

You are driving a high-end car at 80 kmph. The car glides on the road effortlessly. Suddenly a bull crosses the road, you apply the brake. It is a 'bit late'. You hit the bull. The front of the car is damaged. But, no big damages to the car or the passengers. The bull goes away without a scratch because its weight is more than 1000 kg.

The period between the instant of seeing an event and the instant of car coming to a standstill (stop) is the 'reaction time'. The reaction time has two components. 1. Your thinking time 2. car stopping time. During the two time periods, the car would have traveled some distance. One is named 'thinking distance' and the other is 'breaking distance'.

Thinking distance:
Your thinking time is always the same. But thinking distance changes according to the speed of the car.
Thinking distance = car speed in feet per second* your thinking time in seconds.
On highways, it is frequently recommended that you have two seconds gap between you and the car in front of you. It is because thinking distance is important, giving yourself a couple of seconds of space means you should have plenty of time to figure out the situation and stop at the right time.

Breaking distance:
    When the car runs, it carries energy 1/2mv^2, where m is car's mass and v is its speed.  The energy should be brought to zero on stopping.  The brake gives opposite force and reduce the energy.
Breaking distance= square of the speed in mph/20
Total stopping distance:
    At 20 mph, it takes about 40 feet to stop, 20 feet to react to what is going on in front of you and 20 feet to bring the car to a halt.  At 40 mph, it is 120 feet. At 80 mph, the stopping distance is 400 feet.  That is why, driving at 80 kmph is dangerous and not permitted.  Every extra mile per hour (speed) takes an extra foot of stopping distance.
    Please bear in mind, breaking distance and thinking distance while driving. That will save lot of lives and damages.

FOOT NOTE:

1. We are losing 1.325 million lives worldwide every year due to accidents.
2. Stopping distance further increases on wet road.
3. Moderate speed is the key to safe driving.
4. Human visual reaction time is said to be 180-200 milli seconds.

Comments

Your heart -you do not know

Size and Location: The human heart is roughly the size of a clenched fist and is located slightly to the left of the center of the chest. Despite its relatively small size, the heart plays a crucial role in pumping blood throughout the entire body. Heartbeat Variability: The heart does not beat at a constant rate. The interval between heartbeats can vary, and this variability is considered a sign of a healthy heart. Factors such as breathing, emotions, and physical activity influence the heartbeat. Electrical Conduction: The heart's contractions are controlled by electrical impulses. The sinoatrial (SA) node, often called the "natural pacemaker," generates electrical signals that regulate the heartbeat and coordinate the pumping of blood. Blood Pumping Capacity: On average, the human heart pumps about 2,000 gallons (or 7,570 liters) of blood each day. Over a lifetime, this amounts to pumping enough blood to fill several Olympic-sized swimming pools. Heart Chambers and V...

THE WORK HORSE "="

One cannot think of a mathematical step without 'is equal to ' . It balances right hand side and left hand side. It aids simplification and manipulation of a mathematical expression. example: 2(A+B) = C 2A+2B = C 2A = C-2B A = C-2B/ 2 In an electronic calculator, the pressing of ' = " sign executes an asthmatic expression or simply calculates. In computer languages, it plays very important role. A = B When a computer looks at this expression, the value stored in the location named B is just transferred to the storage named A . After execution both A and B will have the same value an...

How does your smart phone detect motion, steps, rotation, and location?

How it works-1 An accelerometer in a smartphone is a microelectromechanical system (MEMS) device that measures acceleration and tilt. It works by detecting changes in motion by measuring the vibration or acceleration of the device. The accelerometer consists of a small mass suspended on a spring inside a sealed chamber. When the device is subjected to acceleration, the mass moves relative to the device, causing a change in capacitance that can be measured and processed by the smartphone's hardware. The accelerometer measures acceleration in three dimensions (x, y, and z) and provides data that the smartphone's software can use to determine the device's orientation, detect motion, and track changes in velocity and acceleration. The accelerometer is used for a variety of purposes in a smartphone, including screen rotation, motion tracking for games and fitness apps, and detecting the position of the device for navigation and location services. Additionally, it can be used t...

sciencecapsules

Search This Blog