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How to find the acceleration?

The term “acceleration” is one of the few, the meaning of which is clear to those who speak Russian. It denotes the value, which measures the velocity vector of a point by its direction and numerical value. Acceleration depends on the force applied to this point; it is directly proportional to it, but inversely proportional to the mass of this point itself. Here are the main criteria for how to find acceleration.

It follows from where exactly the acceleration is applied. Recall that it is denoted as "a". In the international system of units it is considered to be the unit of acceleration value, which consists of an indicator of 1 m / s2(meter per second squared): acceleration at which for every second the speed of the body changes by 1 m per second (1 m / s). Suppose the acceleration of the body is 10m / s2. This means that during each second, its speed changes by 10 m / s. What is 10 times faster if the acceleration was 1m / s2. In other words, speed means a physical quantity that characterizes the path traveled by the body over a certain time.

Answering the question of how to find acceleration, you need to know the way body movement,its trajectory is rectilinear or curvilinear, and the speed is uniform or non-uniform. Regarding the latter characteristic. those. speed, it must be remembered that it can vary vectorially or in absolute value, thereby giving acceleration to body motion.

Why do we need the acceleration formula

Here is an example of how to find the acceleration in speed, if the body starts a uniformly accelerated motion: it is necessary to divide the change in speed by the length of time during which the change in speed occurred. It will help solve the problem, how to find the acceleration, the acceleration formula a = (v -v0) /? T =? V /? T, where the initial velocity of the body is v0, the final velocity is v, the time interval is? T.

On a concrete example, it looks like this: let's say the car starts moving, moving off, and in 7 seconds picks up speed at 98 m / s. Using the above formula, the vehicle acceleration is determined, i.e. taking the initial data v = 98 m / s, v0 = 0,? t = 7c, it is necessary to find what is equal to a. Here is the answer: a = (v-v0) /? T = (98m / s - 0m / s) / 7s = 14 m / s2. We get 14 m / s2.

Search for gravitational acceleration

And how to find the acceleration of free fall? The very principle of the search is clearly seen in this example. It is enough to take a metal body, i.e.an object made of metal, fasten it at a height that can be measured in meters, and, when choosing the height, it is necessary to take into account the air resistance, and this, which can be neglected. Optimally, this is a height of 2-4 m. A platform should be installed below, specifically for this item. Now you can detach the metal body from the bracket. Naturally, it will begin free fall. It is necessary to fix the time of body landing in seconds. Everything, you can find the acceleration of the object in free fall. For this, the given height must be divided by the time of flight of the body. Only this time must be taken in the second degree. The result obtained should be multiplied by 2. This will be the acceleration, more precisely, the value of the acceleration of the body in free fall, expressed in m / s2.

You can determine the acceleration due to gravity using gravity. Measuring the body weight in kg with weights, observing the utmost accuracy, then suspend this body on a dynamometer. The result of gravity will be in newtons. Dividing the value of gravity on the body mass, which has just been suspended by a dynamometer, we get the acceleration of gravity.

Acceleration is determined by the pendulum

It will help to establish the acceleration of gravity and the mathematical pendulum. It is a body fixed and suspended on a thread of sufficient length, which is measured in advance. Now it is necessary to bring the pendulum into a state of oscillation. And using a stopwatch, count the number of oscillations in a certain time. Then divide this fixed number of oscillations by time (it is in seconds). The number obtained after the division, build to the second degree, multiply by the length of the pendulum filament and the number 39.48. Result: the acceleration of free fall was determined.

Acceleration Measuring Instruments

It is logical to complete this information block on acceleration by the fact that it is measured with special devices: accelerometers. They are mechanical, electromechanical, electrical and optical. The range that they can do - from 1 cm / s2up to 30 km / s2, which means O, OOlg - 3000g. If we use Newton's second law, we can calculate the acceleration by finding the quotient from dividing the force F acting on a point by its mass m: a = F / m.


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