Physics Quiz 4

The total energy of an electron in an atom in an orbit is −3.4eV. The total energy is the sum of the electron's kinetic energy (3.4 eV) and the potential energy (-6.8 eV) coming from the electron-proton interaction.

Anemometer is an instrument used to measure the force, pressure and velocity (speed) of the wind. It is an important tool for meteorologists, who study weather patterns.

Frequency determines colour, but wavelength is the easier thing to measure. These wavelengths range from 700 nm at the red end of the spectrum to 400 nm at the violet end. Visible light waves are the only electromagnetic waves we can see.

Herman Hollerith (1860-1929) was a German-American statistician, inventor, and businessman. He was the inventor of the punched card tabulating machine—the precursor of the modern computer—and one of the founders of modern information processing. His machine was used to gather information for the 1890 census more efficiently.

In this case the given equation shows that the velocity is linear with time and therefore the particle is moving with constant acceleration. If you travel with a constant acceleration, your velocity is always changing, but it's changing by a consistent amount each second.

When sunlight incident on raindrops formation of a Rainbow occurs in the sky. These raindrops work as a prism. When sunlight hits a raindrop, some of the light is reflected. The electromagnetic spectrum is made of light with many different wavelengths, and each is reflected at a different angle. Thus, spectrum is separated, producing a rainbow.

Rectilinear propagation describes the tendency of electromagnetic waves (sunlight) to travel in a straight line. Eclipses occur due to the rectilinear propagation of light. Whenever an obstacle is placed in the path of light, the shadow of the obstacle is seen on the other side.

When the ice was floating, the volume of water displaced had a mass equal to that of ice. After melting, that mass of ice has been converted into water. Therefore, there is no change in water level.

A communications satellite's transponder is the series of interconnected units that form a communications channel between the receiving and the transmitting antennas. It is mainly used in communication satellite to receives signals from an earth station and transmits them to different directions.

A concave lens is used to minimize the proportions of the objects and gives a wider view of the object or area. It always forms virtual, erect and diminished image.