Figure 1 shows the electromagnetic spectrum, or the spectrum of energies of light emitted from the sun. The top axis shows each type of electromagnetic wave as a frequency (given in hertz, Hz), where high frequencies correspond with high energy light waves. The bottom axis shows wavelengths (given in meters, m) of each type of light, where short wavelengths correspond with higher energy light waves. There is an inset to show visible light, where higher energy violet light typically has a wavelength around 400nm and 700nm corresponds to lower energy red light. Visible light, as shown in the figure, is typically measured in nanometers (nm), where there are  nanometers per meter.

Figure 1

A scientist studying the types of electromagnetic radiation emitted from the sun compiled data about the intensity of light at various wavelengths. It was found that less than 1% of radiation from the sun is of wavelengths shorter than 100nm or longer than 2500nm. Intensity of radiation at middle wavelengths was graphed in Figure 2. 

Figure 2

As you may know, exposure to ultraviolet light is dangerous as it is energetic enough to degrade DNA, leading to cancer. Assuming that all types of radiation that are more energetic than ultraviolet light are also carcinogenic, what of the following types of light likely cause cancer as well?

Figure 1 shows the electromagnetic spectrum, or the spectrum of energies of light emitted from the sun. The top axis shows each type of electromagnetic wave as a frequency (given in hertz, Hz), where high frequencies correspond with high energy light waves. The bottom axis shows wavelengths (given in meters, m) of each type of light, where short wavelengths correspond with higher energy light waves. There is an inset to show visible light, where higher energy violet light typically has a wavelength around 400nm and 700nm corresponds to lower energy red light. Visible light, as shown in the figure, is typically measured in nanometers (nm), where there are  nanometers per meter.

Figure 1

A scientist studying the types of electromagnetic radiation emitted from the sun compiled data about the intensity of light at various wavelengths. It was found that less than 1% of radiation from the sun is of wavelengths shorter than 100nm or longer than 2500nm. Intensity of radiation at middle wavelengths was graphed in Figure 2. 

Figure 2

Figure 2 shows an appreciable amount of radiation is produced by the sun with a wavelength of 2000nm. What type of radiation is it, and what is its wavelength in meters?

Figure 1 shows the electromagnetic spectrum, or the spectrum of energies of light emitted from the sun. The top axis shows each type of electromagnetic wave as a frequency (given in hertz, Hz), where high frequencies correspond with high energy light waves. The bottom axis shows wavelengths (given in meters, m) of each type of light, where short wavelengths correspond with higher energy light waves. There is an inset to show visible light, where higher energy violet light typically has a wavelength around 400nm and 700nm corresponds to lower energy red light. Visible light, as shown in the figure, is typically measured in nanometers (nm), where there are  nanometers per meter.

Figure 1

A scientist studying the types of electromagnetic radiation emitted from the sun compiled data about the intensity of light at various wavelengths. It was found that less than 1% of radiation from the sun is of wavelengths shorter than 100nm or longer than 2500nm. Intensity of radiation at middle wavelengths was graphed in Figure 2. 

Figure 2

Which of these correctly lists the different types of electromagnetic radiation in order of increasing energy?

Figure 1 shows the electromagnetic spectrum, or the spectrum of energies of light emitted from the sun. The top axis shows each type of electromagnetic wave as a frequency (given in hertz, Hz), where high frequencies correspond with high energy light waves. The bottom axis shows wavelengths (given in meters, m) of each type of light, where short wavelengths correspond with higher energy light waves. There is an inset to show visible light, where higher energy violet light typically has a wavelength around 400nm and 700nm corresponds to lower energy red light. Visible light, as shown in the figure, is typically measured in nanometers (nm), where there are  nanometers per meter.

Figure 1

A scientist studying the types of electromagnetic radiation emitted from the sun compiled data about the intensity of light at various wavelengths. It was found that less than 1% of radiation from the sun is of wavelengths shorter than 100nm or longer than 2500nm. Intensity of radiation at middle wavelengths was graphed in Figure 2. 

Figure 2

Which of the following types of light are emitted in spectral irradiances of greater than ?

I. Visible light

II. Gamma rays

III. Microwaves

Engineers are evaluating four potential technologies. These technologies are to be used as power plants that are considered "clean" energy. The estimated energy output of these plants were calculated and the resources needed to run these were also listed. 

What is the expected energy output, in kiloWatt hours per a day, if there were no resource limitations? 

A company developed new prototype car and wanted to test the new car. The car's acceleration time from 0mph to 60mph and stopping time from 60mph to 0mph were measured. An obstacle course involving a lot of turns was also constructed to determine how well the car can handle turning. The main concern of the company is the safety of the car and therefore all of the tests were performed on dry concrete, concrete after simulated rain, concrete that was covered with snow and in sand. 

What is the relationship between stopping time and obstacle course time? 

A student conducts an experiment in which she suspends a ball mass  from a string and swings it in a perfect circular motion. What is often referred to as centrifugal force appears to push the ball away from the center of the circle of its motion with a force   in the string. The force is described by the formula  where  is the mass,  is the speed of the ball, and  is the radius of its motion.

The student first tries the experiment spinning the ball at a speed of . The resulting force is . What would the force in the string be if she sped up the ball to a speed of ?

A student conducts an experiment in which she suspends a ball mass  from a string and swings it in a perfect circular motion. What is often referred to as centrifugal force appears to push the ball away from the center of the circle of its motion with a force   in the string. The force is described by the formula  where  is the mass,  is the speed of the ball, and  is the radius of its motion.

Which of the following could be a graph of force in the string as a function of radius ?

Sometimes scientists need to scale down experiments because collecting full-scale data may not be practical or possible. Most of the time, the data collected during a small scale-experiment is an accurate indicator of full-scale results. For example, research of craters on the Earth’s surface has indicated that the Earth has experienced a history of massive meteor collisions. It has been hypothesized that, amongst other things, these impacting meteorites caused the Earth’s oceans to vaporize. The detrimental effects associated with meteor collisions would have made the planet to be uninhabitable to humans. Due to these adverse effects, an experiment that could produce meteor-sized craters would not be possible in a full-scale setting.

Researchers have developed small-scale experiments that are exemplary of Newton’s three laws of motion. Newton’s first law states that an object in motion will stay in motion unless it is acted on by another force. This phenomenon is known as inertia. The second law comes in the form of an equation that calculates how much force is exerted on two colliding objects with respect to mass and acceleration. In other words force is equal to the mass of an object multiplied by its acceleration. The third law states that for every action there is an equal and opposite reaction. In other words, forces always occur in pairs. A counter force that is equal in magnitude and opposite in direction compliments each force in a particular direction. For example, if you push downwards on a table then the table, in theory, pushes upwards with the same force.

In a particular small-scale exercise, students were asked to design an experiment in which two “meteorites” would be dropped into a medium of sand and the subsequent crater diameters would be measured. Afterwards, the sand would be leveled and the experiment would be repeated. The students were asked to identify all of the factors that could affect the formation of the craters. This was done in order to ensure that each experiment was testing one independent and one dependent variable at a time. Otherwise, it would be unclear which variable is causing the observed effect. Possible variables that could alter the outcome of the experiment included but were not limited to the following: height of the fall, speed of the “meteorite,” angle of impact, and the mass of meteorite.

Consider an experiment that seeks to identify the mass of the meteorite analog. All other variables would have to remain constant in order to ensure accurate results.  In order to do this, the height of the fall was set to one meter. The object was placed on top of a vertical meter stick. In order to keep the acceleration and height of the drop constant, it was rolled off of the stick instead of being pushed or simply dropped. Last, a protractor was used to keep the meter stick at a ninety-degree angle. In the procedure, a marble and a golf ball were used as “meteorites” of different masses.

The results of the experiment were recorded in the table and figure provided.

The equation for kinetic energy (energy in motion) is as follows:

In this equation, kinetic energy equals one half of the mass of the object times its velocity squared. Based on this information, identify what would happen to the force of the impact if the velocity is quadrupled?

Sometimes scientists need to scale down experiments because collecting full-scale data may not be practical or possible. Most of the time, the data collected during a small scale-experiment is an accurate indicator of full-scale results. For example, research of craters on the Earth’s surface has indicated that the Earth has experienced a history of massive meteor collisions. It has been hypothesized that, amongst other things, these impacting meteorites caused the Earth’s oceans to vaporize. The detrimental effects associated with meteor collisions would have made the planet to be uninhabitable to humans. Due to these adverse effects, an experiment that could produce meteor-sized craters would not be possible in a full-scale setting.

Researchers have developed small-scale experiments that are exemplary of Newton’s three laws of motion. Newton’s first law states that an object in motion will stay in motion unless it is acted on by another force. This phenomenon is known as inertia. The second law comes in the form of an equation that calculates how much force is exerted on two colliding objects with respect to mass and acceleration. In other words force is equal to the mass of an object multiplied by its acceleration. The third law states that for every action there is an equal and opposite reaction. In other words, forces always occur in pairs. A counter force that is equal in magnitude and opposite in direction compliments each force in a particular direction. For example, if you push downwards on a table then the table, in theory, pushes upwards with the same force.

In a particular small-scale exercise, students were asked to design an experiment in which two “meteorites” would be dropped into a medium of sand and the subsequent crater diameters would be measured. Afterwards, the sand would be leveled and the experiment would be repeated. The students were asked to identify all of the factors that could affect the formation of the craters. This was done in order to ensure that each experiment was testing one independent and one dependent variable at a time. Otherwise, it would be unclear which variable is causing the observed effect. Possible variables that could alter the outcome of the experiment included but were not limited to the following: height of the fall, speed of the “meteorite,” angle of impact, and the mass of meteorite.

Consider an experiment that seeks to identify the mass of the meteorite analog. All other variables would have to remain constant in order to ensure accurate results.  In order to do this, the height of the fall was set to one meter. The object was placed on top of a vertical meter stick. In order to keep the acceleration and height of the drop constant, it was rolled off of the stick instead of being pushed or simply dropped. Last, a protractor was used to keep the meter stick at a ninety-degree angle. In the procedure, a marble and a golf ball were used as “meteorites” of different masses.

The results of the experiment were recorded in the table and figure provided.

Which of the following best describes how mass changes for varying kinetic energies when the velocity remains constant?