1 -
Dynamometer: instrument used to measure forces. It was invented by Isaac Newton and should not be confused with the balance (instrument used to measure masses), but comparable to the scale.
These instruments generally consist of a spring contained in a cylinder of plastic, cardboard or metal usually with two hooks, one on each end. Dynamometers have a scale marked in units of force, in the hollow cylinder that surrounds the spring. By hanging weights or exerting a force on the crossbar, the lower cylinder cursor moves on the outer scale, indicating the value of force.
springs that form the dynamometers have an elastic limit, so that if they apply very large forces and excessive elongation occur, it can exceed the yield stress, in these conditions, the spring undergoes a permanent deformation which involves the disablement of the dynamometer.
Scale: is a first-class lever with equal arms that by establishing an equilibrium between the weights of two bodies can measure masses. Like a Roman, or a scale, a measuring instrument to measure the mass of an object.
performing measurements using mass standards whose degree of accuracy depends on the accuracy of the instrument. Like a Roman, but unlike a scale or dynamometer, the results of measurements not vary with the magnitude of the acceleration of gravity.
The measurement range and accuracy of a scale can vary from several kilos (to the nearest gram) in industrial and commercial scales, up to a few grams (to the nearest milligram) in laboratory balances.
Caliber: is an instrument for measuring dimensions of relatively small objects, from centimeters to fractions of a millimeter (1 / 10 of a millimeter, 1 / 20 of a millimeter, 1 / 50 of a millimeter). On a scale of inches is divisions equivalent to 1 / 16 of an inch, and, noni, 1 / 128 inch.
is an extremely delicate and must be maneuvered with skill, care and delicacy, careful not to scratch or bend (in particular the depth coliza).
2 -
unit mass International System (SI) is the kilogram (kg) different metric units are therefore expressed :
| 1 ton | (t) | = 1,000,000 g |
| a kilogram | (kg) | = 1 000 g |
| 1 gram | (g) | = 1 g |
| 1milligramo | (mg) | = 0.001 g |
| 1microgramo | (g) | = 0.000 001 g |
| 1nanogramo | (ng) | = 0.000 000 001 g |
| 1picogramo | (pg) | = 0.000 000 000 001G |
The unit of weight or Strength Internaiconal System (SI) is the Newton (N) is the force applied to a body that has a mass of 1kg, tells an acceleration of 1 meter per second.
1 newton = 100 000 dynes
1 kilogram-force = 9.806 65 newtons
1 pound ≡ 4.448 222 newtons force
The unit volume of the International System (SI) is the cubic meter. But there are other units such as:1 dm 3 = 1 liter
1 dm 3 = 1,000 cm 3
3 -
To calculate the mass of the black and silver spheres, we must apply the formula: P = mg m = P / g
68.5 grams · 1kilogramo/1000gramos ← = 0.0685 kilograms on the scale measured data.
silver dial Mass: 0.665 N / 9.8 m / s ² 0.06785 kg → ← data calculated by us.
22.5 grams · 1kilogramo/1000gramos ← = 0.0225 kilograms on the scale measured data.
mass black dial : 0.22 N / 9.8 m / s ² 0.02244 kg → ← data calculated by us.
There is little difference between the measured data on the scale and those obtained by us through the formula m = P / g. In the mass of the silver dial is a difference of 0.00065 kg, and the black area of \u200b\u200b0.00006 kg. Therefore these differences are negligible.
diameter silver and black areas is 2.5 cm + 0.02 cm = 2.52 cm.
In both areas, the value is 2.52 inches.
4 -
First to calculate the volume, we should take the measure of the radio. So if we know the diameter of both areas is of 2.52 cm, the radius is 1.26 cm, and have the same volume.
V = 4 / 3 ° π → · 1.26 cm ³ V = 4 / 3 ° 3.14159 2.000376 · → V = 8.38 cm ³
To calculate the densities of the areas we use the data mass and divide between the volumes.
silver dial Density: 0.068 kg / cm ³ = 8.38 0.00809 kg / cm ³ ← 8.09 × 10 - ³ (to the minus three)
Density black dial: 0.022 kg / cm ³ = 8.38 0.0027 kg / cm ³ 2.68 · ← 10 - ³ (to the minus three)
Now let's move the units of the density g / L.
silver dial Density: 0.0081 kg / cm ³ · 1000gramos/1kg · 1000cm ³ / 1L → D = 8090 g / L.
black dial Density: 0.0027 kg / cm ³ · 1000gramos/1kg · 1000cm ³ / 1L → D = 2678 g / L.
We believe that silver sphere may be composed steel, since this density is 0.0078 kg / cm ³ and our sphere of 0.0081 kg / cm ³.
The black dial believe that is composed of aluminum because it is density of 0.0027 kg / cm ³ and our sphere of 0.0027 kg / cm ³.
5 -
theoretical values \u200b\u200bare obtained by applying the formula of Archimedes: push = V (volume) · G (gravity).
Silver dial:
Push = 8.37 cm ³ · 1gr/cm ³ · 9.81 m / sec ² → E = 82.10 gr · m / sec ²
Now we have to pass grams to kilograms, 82.1 therefore must be divided by 1000 = 0.082 N
black dial:
Push = 8.18 cm ³ · 1g / cm ³ · 9.81 m / sec ² → E = 80.24 gr · m / sec ²
also now have to move the grams to kilograms, because the thrust is shown in Newtons: 80.24 / 1000 = 0.08 N.
The experimental values \u200b\u200bobtained from the data that give us the mass of each ball. We subtract the initial mass before putting the ball in the bowl of water, the final mass after it is introduced.
Silver dial: initial mass final mass = 0.67 N = 0.59 N
E = 0.67 to 0.59 = 0.08 N
Black dial: initial mass final mass = 0.22 N = 0.14 N
E = 0.22 to 0.14 = 0.08 N
There is hardly discrepancy between the results we have obtained and theoretical values \u200b\u200band experimental values \u200b\u200bso we can verify that the assumptions made by Archimedes are correct.
0 comments:
Post a Comment