Physics Problems: Solutions and Explanations
1. Which of the following statements is correct? Functions of the form y = kxn always give a straight line when plotted on logarithmic paper.
2. Note which of the following results is correct, based on the theory of computation error: (0.23)3 = 0.012.
3. In an experiment, a ball of plasticine falls from a height H = 3.00 ± 0.02 m. The gravity is g = 9.81 ± 0.01 ms-2. If errors are given by uncertainties, the velocity of the ball just before impact with the ground is closer to 7.67 ± 0.03 ms-1.
4.
Read MoreUnderstanding Light: From Ancient Theories to Modern Physics
The Nature of Light
The nature of light has always interested humankind. Scientists, philosophers, and thinkers have attempted to answer seemingly simple questions, such as “What is light made of?” since the oldest civilizations. Science, particularly physics, has no simple answers to these questions. For example, to answer that light consists of photons does not respond unless one agrees on the meaning of the word photon. A photon is not an object that belongs to our ordinary experience, like a
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Nature of Light
Newton’s Corpuscular Theory
Light has particle nature: light bulbs emit tiny particles that propagate in a straight line in all directions, colliding with our eyes, producing the sensation of light. Corpuscles, other than for color, can pass through transparent media and are reflected by opaque bodies. This hypothesis justifies phenomena such as the rectilinear propagation of light and reflection, but not refraction.
Huygens’ Wave Theory
Huygens proposed that light consists of wave propagation
Read MoreUnderstanding Laboratory Materials and Earth Sciences
Module 2
The Material in the Laboratory
1 – What is porcelain used for? (Fig. 23)
For heating solutions to dryness. Heat until the solvent is completely eliminated.
2 – Basis of Crystallization.
It is the difference in solubilities at different temperatures.
Example: We have 100 g of water at 80 ºC, which can dissolve 60 g of substance. Now, if we have 100 g of water at 15 ºC, it can dissolve 20 g of substance. If we prepared the solution at 80 °C and left it to cool to 15 °C, 60 g – 20
Understanding Technical Drawing Concepts and Applications
1 – Difference Between Cuts and Sections in Technical Drawing: In the section, we illustrate the intersection between the plane surface drying and solid, while in the case of a cut, we depict the intersection and all that is behind the shear plane.
2 – Definition of Surface Slope: A developable ruled surface is a director cone of revolution. It is a type of surface with equal slope, assuming a curve in space, flat or warped. The points of this line are chosen as vertices of cones that remain homothetic
Read MoreUnderstanding Sound Waves: Properties and Characteristics
Audible Sound Waves
Sound: A longitudinal mechanical wave that propagates through an elastic medium.
A physical disturbance that propagates in an elastic medium such as air.
The sound spectrum is divided into three frequency ranges:
- Audible
- Infrasonic
- Ultrasonic
These intervals are defined as follows: the audible sound corresponds to sound waves in a frequency range of 20 to 20,000 Hz.
Sound waves having frequencies below the audible range are called infrasound.
Sound waves having frequencies above the audible
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