HW Ch. 17-20

Two pools of water contain the same depth of water but one has a blue bottom and the other red. When looking into the pools from above,

the red bottom pool appears deeper.

The "half-life" of a large collection of radioactive nuclei is

the time for half of the collection to decay.

The word "radioactive" means

there are nuclei present which will spontaneously emit nuclear radiation.

In nuclear fusion,

two smaller nuclei combine to form a larger nucleus.

A ray of light traveling in a calm pond strikes the surface at an angle of incidence which is 2° larger than the critical angle. This ray will

undergo total internal reflection and not enter the air at all.

In normal use, the image seen through eyeglasses is

virtual

A plane mirror will always produce a

virtual, erect image.

What is the source of the energy released in nuclear reactions?

The conversion of mass to energy.

A ray emerges from water (n = 1.33) into air. The light ray will

bend away from the normal on the air side.

A rainbow shows separate colors of the spectrum because, at raindrop surfaces,

blue light is bent more than red light.

The focal point of a lens is determined by

both shape and index of refraction.

The focal length of a glass lens depends on

both the curvature of the surface of the lens and the index of refraction of the glass.

Strong x-ray beams can be produced when

cathode rays strike a metal anode.

A shaving mirror and a make-up mirror both magnify the image. Thus, these mirrors are ___________ mirrors.

concave

A prism decomposes incident white light into its ________________ colors because of refraction.

constituent

Parallel light incident on a positive lens will ___________ as it emerges.

converge

The cornea of the human eye is an example of a

converging lens.

A curved mirror that cannot produce a real image of an object is

convex

The rearview mirror of an auto bears the legend "Objects in mirror are closer than they appear." This mirror is a ______ mirror.

convex

Rays from a distant object do not diverge enough for a nearsighted person to focus; this can be corrected with a

diverging or negative lens.

A nearsighted person requires glasses with lenses that are

diverging, to see distant objects.

The force that holds electrons within atoms is the

electrical force with the nucleus.

A "gamma" ray is

electromagnetic radiation.

X-rays are ___________ waves of _________ wavelength.

electromagnetic, short

The image produced by a single diverging lens will ALWAYS be

erect and virtual.

The Tokamak is a type of

experimental fusion reactor.

The energy of a photon is calculated from the product of the constant h times the ________________.

frequency

A fish looks up through the smooth surface of the water at a bear directly above it. To the fish, the bear appears to be

further away than it really is.

A deuterium nucleus and a tritium nucleus react to yield one alpha particle, a neutron, and energy. This is an example of a

fusion reaction.

The three types of nuclear radiation are

gamma, beta, alpha.

If h = Planck's constant, the de Broglie wavelength of a particle of linear momentum p and kinetic energy KE is given by the following formula:

h/p

Different atoms in the same column of the periodic table of elements

have similar chemical properties.

The substance that comes from a nuclear reactor which is used to generate power is

high-pressure steam.

The discovery of the neutron helped people understand

how two atoms of the same element can have different atomic masses.

The unaided nearsighted human eye focuses light from a distant object

in front of the retina.

A converging lens

is thicker in the center than the edges.

Two nuclei have the same number of protons but different numbers of neutrons. We call these two nuclei

isotopes.

Light is refracted as it crosses the interface between two different media because

it changes speed.

The energy of a photon is proportional to

its frequency.

A Jurassic dinosaur is approaching your vehicle and appears in the side-view mirror. It is larger than it appears in the mirror. This means that

its image size is smaller than what the flat rearview mirror shows.

In order for a telescope to produce a large magnification one would select lenses of

large focal length for the objective and short focal length for the eyepiece.

During radioactive decay, the daughter element is always

less massive than the parent.

Some substances emit radiation without any need to expose the material to other energy sources. We call these substances

naturally radioactive.

Glasses prescribed to correct a nearsighted eye will have a _______________ (sign) focal length.

negative

The magnification produced by a plane mirror is ____________ (sign and magnitude).

+1

Light enters water (n = 1.33) from air. The incident light ray makes a 0.44° angle with the normal to the surface on the air side. What will be the angle made with the normal by the refracted ray on the water side?

0.33°

A woman 1.6 m in height wants a plane mirror so that she can view her full height. The minimum vertical size of such a mirror is

0.8 m.

This form of natural radioactivity will be deflected by a magnetic field.

Alpha rays

The speed of light in a certain type of glass is 30% slower than the speed of light in air. What is the index of refraction for that type of plastic?

1.43

When one observes a scratch on the bottom of a block of clear plastic, the scratch appears to be 2.5 cm below the top surface as viewed from above. The actual thickness of the plastic block is 3.0 cm. The index of refraction of the block is

1/2

A 1 cm object is placed 20 cm from a lens. The lens forms a real and inverted image of size 1.5 cm. What is the focal length of the lens?

12 cm

If 42 g of nitrogen reacts completely with 9 g of hydrogen (atomic mass 1) to form ammonia (NH3), the atomic mass of nitrogen must be

14

An object is placed 10 cm in front of a concave mirror of focal length 30 cm. The image will be formed

15 cm behind the mirror.

The maximum number of electrons allowed in the n = 1 shell of sodium is

2

An object is placed 10 cm in front of a diverging lens of focal length -15 cm. The image will be located

6.0 cm in front of the lens.

The N14 nucleus consists of

7 protons and 7 neutrons.

Chapter 18

Chapter 18

Chapter 19

Chapter 19

Fiber optics in a DVD player contain their light by employing total internal reflection. Designers surround the pure glass core with another type of glass, called cladding, that has a different index of refraction from the core. How should you select a cladding?

Cladding must have a smaller index of refraction than the core.

Which of the following optical elements used alone can produce a real image of an object?

Concave mirror

Which is the smallest entity in the following list?

Electron

The Bohr theory of the atom made the following BOLD assumption:

Electrons in certain orbits do not radiate electromagnetic waves despite being centripetally accelerated.

Cathode rays produced in a gas discharge tube are

Electrons.

Total internal reflection can occur when a light ray moves across a boundary between different materials in which direction?

From a material with a slower speed of light to a material with a faster speed of light

Which of the following individuals did not directly contribute to quantum theory?

Roentgen

The objective lens of a high-power microscope will have a ___________ (large, short) focal length and will be a __________ (converging, diverging) lens.

Short,converging

A ray of light in plastic reaches the edge of the plastic. The medium surrounding the plastic is air and the angle of incidence is larger than the critical angle. What will happen?

The ray will experience total internal reflection, the angle of reflection equaling the angle of incidence.

The electron was discovered by ________________ (one name) in his study of ____________________ (two words).

Thomson , Cathode rays.

Convex (converging) lenses are worn by

a farsighted person to make rays from a nearby object diverge less strongly.

When light enters a medium with a higher index of refraction it

is bent towards the normal.

In nuclear fission,

a nucleus is split into two less massive nuclei.

The image viewed in a telescope is a magnified virtual image. To achieve this, a telescope must have

a positive eyepiece lens with a small focal length.

One of the fundamental ideas in the development of quantum mechanics was that

all particles have wave properties.

One of the patterns that shows up nicely in the periodic table is that similar chemical properties

are displayed by elements in the same column.

A real image of a candle formed with a converging lens can be viewed on a screen placed

at a single position determined by the distance of the object and the construction of the lens.

A chemical reaction is one in which

atoms get rearranged.

Light passing from glass into air bends _________________ (toward, away from) the normal to the surface because it is traveling ____________ (slower, faster) in the glass than in air.

away from,slower

One ray that is useful in locating the image formed by a convex mirror is the ray that is incident on the mirror in a path directed toward the focal point. This ray is reflected

on a path parallel to the mirror axis.

In the primary or inner rainbow, the

outer edge of the bow appears red and the inner edge appears blue or violet.

When an atom has an electron removed, then its net charge is

positive.

Both conventional fossil fuel and nuclear power plants

produce waste heat that can affect the weather or upset the ecology of rivers or lakes.

A primary waste product of nuclear reactors that are designed for only power generation is

radioactive materials.

The image formed by a concave mirror when the object distance is greater than the focal length is always

real

The image of an object placed 20 cm in front of a concave mirror of focal length 10 cm will be

real and inverted.

One difference between a microscope and a telescope is that the image formed by the objective is

real for both, but the image is enlarged for the microscope and reduced for the telescope.

An object is placed in front of a concave mirror. The object is farther from the mirror than the focal length of the mirror. The type of image reflected from the mirror is __________ and the orientation of the image is ___________.

real, inverted

In a nuclear reactor, "chain reaction" refers primarily to

the process by which the fission of one nucleus causes other nuclei to undergo fission.

The purpose of the moderator in a reactor is to

slow neutrons down so that they will be more likely to initiate fission reactions.

If the image formed by a concave mirror is closer to the mirror than the object is, then, compared to the object, the image will be

smaller and inverted.

Dalton developed _________ as one of the foundations for the atomic theory.

the Law of Definite Proportions

When light is reflected from a smooth, plane mirror

the angle of reflection is the same as the angle of incidence.

A raindrop is doing its part to form a primary rainbow. Red and blue light enter near the top of the raindrop together from the sun. Both red and blue are reflected once at the back surface of the drop, but when the two rays emerge on the sunward side

the blue ray lies above the red ray and is more nearly horizontal than the red ray.

The number of protons in the nucleus of an atom determines

the density of the nucleus.

If h = Planck's constant, the frequency of light emitted when an atom makes a transition is equal to

the energy lost by the electron divided by h.

Light from the sun passes through a converging lens and forms an image at

the focal point.

An iPod is 20 cm in front of a flat mirror. You see the reflected image and must refocus your eye, perhaps even take off your eyeglasses, because

the image location is 20 cm behind the mirror.

A beam of white light in air passes through the transparent object shown. Dispersion is observed to occur. From the diagram we can tell that

the index of refraction is larger for red light than blue.

The systematic arrangement of all known elements is known as

the periodic table of elements.

Lenses can be used to focus sunlight to a small point to burn paper or dry brush. A person demonstrates this using their own eyeglasses as the lenses. From this you can tell that

the person is farsighted.