8Th Physical Science PHYSICS PART 2 STUDY GUIDE

8th Physical Science PHYSICS PART 2 STUDY GUIDE

1)Gravity on the moon is about1/6ththe gravity felt on the earth. This is because

A) / the moon is so far away from the earth.
B) / the moon is much less massive than the earth.
C) / the earth has a molten core and the moon doesn't.
D) / the moon is so much further from the sun than the earth.

2)Ultraviolet radiation is dangerous because it has a high enough energy to damage skin cells. UV radiation is called ultraviolet because it has a frequency which is higher than violet radiation (purple light). Therefore, it has a wavelength which is ______than violet radiation.

A) / bigger
B) / smaller
C) / the same size
D) / the square root of

3)An echo is an example of sound wave

A) / diffraction.
B) / interference.
C) / reflection.
D) / refraction.

4)The picture lists light waves from left to right in order of highest to lowest energy. Which region of the electromagnetic spectrum has the longest wavelength?

A) / UV
B) / Gamma Rays
C) / Radio Waves
D) / Visible Light

5)After turning off the television, you approach it. As you get close, but not touching it, the hairs on your arm start to stand up. This is an excellent example of static charge built up by

A) / conduction.
B) / convection.
C) / friction.
D) / induction.

6)A scientist is giving a demonstration with a Van de Graaff generator in a class about static electricity. The scientist can detect the type of charge on the Van de Graaff generator by

A) / bringing a positively charged balloon near it.
B) / seeing if it picks up bits of paper from a surface.
C) / touching it with a metallic rod that conducts charge.
D) / testing if it attracts a neutral sphere made of plastic.

7)Which form of radiation from the electromagnetic spectrum is MOST LIKELY to cause mutations in growing tissues, and should be MOST avoided by pregnant women?

A) / microwaves
B) / gamma rays
C) / radio waves
D) / ultraviolet rays

8)You attend a football game one day and notice a long time difference between when the other side of the stadium stands up to cheer and when you hear them. This time difference would be lessened if

A) / it were warmer.
B) / it were less humid.
C) / it were located at a higher altitude.
D) / the fans on the opposite side shouted louder.

9)The speed of sound is greater through a solid than through a gas because the molecules in a solid are

A) / still.
B) / vibrating.
C) / farther apart.
D) / closer together.

10)The circumstance MOST LIKELY to cause a compass to give an erroneous reading is standing too close to

A) / the ocean.
B) / a mountain.
C) / an electric power line.
D) / a heavily populated area.

11)Longitudinal waves compress the medium they travel though. One example of a longitudinal wave is a

A) / sound wave.
B) / ocean wave.
C) / infrared wave.
D) / ultraviolet wave.

12)Sal and Marie were experimenting with bar magnets in science class, picking up chains of paper clips. Where should they expect the magnetic force of the bar magnet to be the strongest and pick up the most paper clips?

A) / at both Poles
B) / at the South Pole
C) / at the North Pole
D) / in the center of the bar magnet

13)The distance shown in the diagram is known as the

A) / amplitude.
B) / crest.
C) / trough.
D) / wavelength.

14)What factor is responsible for altering the speed of an electromagnetic wave?

A) / amplitude
B) / wavelength
C) / type of medium
D) / frequency of the wave

15)It seems like everyone has a cell phone these days. Sounds, images, and the written word can all instantly be sent using this technology. How do cell phones send information from one person to another?

A) / Sound waves are sent through the air.
B) / Sound waves are sent through overhead cables.
C) / The signals are sent through underground cables.
D) / The signals are sent through communication satellites.

16)______lenses refract light rays in toward a central point. When this lens is held close to your eye, the image is magnified and right side up.

A) / Concave
B) / Convex
C) / Prismatic
D) / Refractive

17)As a marching band passed by, the beating drums and trumpets made Billy feel like his body was beating with the music. He could hear the music and he could feel it!
How would a scientist explain this to Billy?

A) / Sound waves cannot travel through the air
B) / Sound waves transmit energy through all forms of matter.
C) / The marching causes the ground to move which Billy feels
D) / Sound waves are transmitted faster through gases than through solids.

18)When Jamie removes a woolen cap, his hair develops an excess of static charge Which of these BEST explains this phenomenon?

A) / Electrons are transferred from the woolen cap to Jamie’s hair.
B) / Electrons are transferred from Jamie’s hair to the woolen cap.
C) / Positive charges are transferred from the woolen cap to Jamie’s hair.
D) / Positive charges are transferred from Jamie’s hair to the woolen cap.

19) The figure shows a negatively charged sphere and a balloon that has been rubbed with dry human hair. If the two are brought close to each other but do not touch each other, you can predict that the objects will

A) / repel each other.
B) / charge each other.
C) / attract each other.
D) / polarize each other.

20)Maria and Sarah made a set of paper cup telephones. First the girls punched a hole in the bottom of each cup. Then they connected the cups with a very long piece of string, knotted in the bottom of each cup. Maria went down the hall to her bedroom while Sarah stayed in the kitchen. When Maria put the cup to her ear she could hear Sarah talking to her because.

A) / they were not that far from each other.
B) / sound waves traveled through the string to Maria’s cup.
C) / sound waves traveled through the air from room to room.
D) / sound waves bounced off of the walls to reach Maria in the bedroom.

21)Which phenomenon causes an object to appear bent from above the surface of one medium to below the surface of another medium?

A) / diffraction
B) / dispersion
C) / reflection
D) / refraction

22)What happens when light strikes a transparent object?

A) / All the light passes through the object
B) / None of the light passes through the object
C) / All of the light is reflected then reabsorbed
D) / Some of the light is scattered or absorbed and some passes through.

23)Sara is using a magnifying glass to closely examine her stamp collection. Why type oflensis found in a magnifying glass?

A) / bifocal
B) / concave
C) / convex
D) / prismatic

24)Reflection is the bouncing of light rays off of a surface. Which situation is NOT an example of reflection?

A) / looking at yourself in a mirror
B) / focusing light through a camera lens
C) / seeing an image of yourself in a still lake
D) / looking at your teacher at the front of the class

25)Which change would result in a stronger electromagnet?

A) / using a smaller battery
B) / using an iron nail with a larger diameter
C) / changing the core to something made of aluminum
D) / decreasing the number of wire coils around the nail

26)

Reva placed an iron nail close to a magnet. What happened?

A) / The nail bent.
B) / The nail moved to the magnet.
C) / The nail stayed in the same place.
D) / The nail pushed away from the magnet.

27)A convex lens bulges outward in its center. and it refracts light rays towards its center. Which represents a convex lens?

A) / A
B) / B
C) / A and B
D) / neither A nor B

28)Mary touched the Van de Graaff generator and all her hair stood on end. The charge from the generator was transferred to Mary's hair so all of the strands had thesame+ charge. Her hairs all repelled each other and stood on end like you see here. This illustrates what law?

A) / law of gravity
B) / law of electrons
C) / law of attraction
D) / law of electricity

29)Brady connected the lose wire to the battery and created an electromagnet. He picked up 45 thumb tacks with his electromagnet, though his goal was to pick up 50 thumb tacks. What could Brady do to increase the strength of his electromagnet and pick up more thumbtacks?

A) / Use fewer coils of wire.
B) / Use a screw instead of a nail.
C) / Use two batteries instead of one.
D) / Replace the nail with a piece of steel.

30)CD's and DVD's both are applications of light. Light is used to read the information on the disc. Which property of light is used in this technology?

A) / Diffraction
B) / Interference
C) / Reflection
D) / Refraction

31)What statement explains the changes from wave A to wave B?

A) / The energy and amplitude increase.
B) / The energy and amplitude decrease.
C) / The energy decreases as the amplitude increases.
D) / The energy increases as the amplitude decreases.

32)Sound travels in waves. Sound waves cannot travel through

A) / air.
B) / solids.
C) / space.
D) / water.

33)Which choice BEST represents the sound waves from a soft low-pitched train rumble that suddenly shifts to a loud, high-pitched squeal of brakes?

A)
B)
C)
D)

34)Eyeglasses bend light help the image form properly on the retina. The bending of light as it passes from one medium to another is called

A) / diffraction
B) / interference
C) / reflection
D) / refraction

35)

Based on the images seen here, identify which phase of matter would transmit sound waves the fastest, and why?

A) / The gas would transmit the fastest because the particles move the fastest.
B) / The solid would transmit the fastest because the particles are closest together.
C) / The liquid would transmit the fastest because the particles are the most freely moving.
D) / The gas would transmit the fastest because there are the fewest particles to interfere with the waves.

36)If your new bike is painted so that it looks red, what color of light is reflected by the paint?

A) / blue
B) / indigo
C) / red
D) / violet

37)

In the old west, a cowboy would put their ear on the railroad track to determine if a train was coming. Using this method, they could tell if the train was coming sooner than just listening for the train.

A good explanation for this would be that

A) / sound and vibrations travel faster through gases than solids.
B) / sound and vibrations travel faster through solids than gases.
C) / sound and vibrations dissipate faster in solids than in liquids or gases.
D) / sound and vibrations are more concentrated in solids than in liquids or gases.

38)You rub a balloon on your head and it becomes negatively charged. The balloon will be MOST attracted to

A) / a piece of metal.
B) / positively charged hair.
C) / the neutrally charged wall.
D) / another negatively charged balloon.

39)Mrs. Adams class decides to try an experiment. She rubs a blown up balloon on Sandy's head. After this, she takes the balloon and places it on the side of the wall, where it sticks, instead of falling to the ground. Also, Sandy's hair is now sticking almost straight out.
What causes Sandy's hair to act this way?

A) / magic
B) / wind currents
C) / static electricity
D) / current electricity

40)

A table has several directional compasses, several lengths of wire, an iron nail, a battery, an ammeter, a light bulb, a permanent magnet, several metal paper clips and a rubber eraser.

A student is asked to build and demonstrate a working temporary magnet. From the items on the table, which items can be used together to accomplish this task?

A) / A battery, an iron nail, a wire and several paper clips will accomplish this task.
B) / An ammeter, an iron nail, a wire and several paper clips will accomplish this task.
C) / A battery, a wire, a permanent magnet and several paper clips will accomplish this task.
D) / A battery, an iron nail, a permanent magnet and several paper clips will accomplish this task.

41)A high school website directs parents to not allow student access to blue laser pointers or allow the students to bring them to school. It includes a video describing the danger inherent in the misuse of all laser pointers particularly the blue laser pointer. Why would they claim that blue laser pointers are more of a concern than red laser pointers?

A) / Colored light falls into the visible region and the red light has a smaller wavelength and higher energy than blue light.
B) / The wavelengths and energies differ. The ultraviolet blue light has a larger wavelength and smaller energy compared to infrared.
C) / Both wavelengths fall into the visible light region but blue light has a smaller wavelength and higher energy than red light.
D) / These colors have similar wavelengths but the blue laser light has more energy than red laser light making it more dangerous.

42)A Wi-Fi hotspot is an area with an accessible wireless network. The term is most often used to refer to wireless networks in public areas like airports and coffee shops. Some are free and some require fees for use, but in either case they can be handy when you are on the go. Just like cellphones and televisions, wi-fi works by utilizing ______to transmit signals and data.

A) / radio waves
B) / microwaves
C) / ultraviolet rays
D) / infrared waves

43)Mary's class is studying sound waves. Mary played two sounds on her flute. For the first sound, Mary blew gently. For the second sound, Mary blew into the flute with a lot of force. What change can you hear?

A) / The second flute sound is louder than the first.
B) / The first flute sound has a higher pitch than the second.
C) / The two flute sounds are the same because they are the same note.
D) / The second flute sound has a lower pitch and is louder than the first sound.

44)A remote control only works when it is pointed at the television. What is the best explanation for this?

A) / The remote control has a weak signal and will only work over short distances.
B) / The remote control transmits information at the speed of light to the television.
C) / The remote control transmits information that is encoded and the television decodes it.
D) / The remote control transmits information through waves, such as infrared waves, to the television.

45)The harder you strike a drum, the greater the sound’s

A) / medium
B) / volume
C) / frequency
D) / pitch

46)Examine the pattern of the wave shown. What is true about the amplitude and wavelength of the wave when the pattern changes?

A) / Both the amplitude and wavelength of the wave increase.
B) / Both the amplitude and wavelength of the wave decrease.
C) / The amplitude of the wave increases while the wavelength decreases.
D) / The amplitude of the wave decreases while the wavelength increases.

47)A concave lens has an inward curved shape. It refracts light outward from the lens. The light rays spread apart as they exit the lens. Which represents a concave lens?

A) / A
B) / B
C) / A and B
D) / neither A nor B

48)A student looks at ocean waves coming into the beach. An ocean wave with more energy will

A) / have a greater height.
B) / have a greater period.
C) / travel toward the beach faster.
D) / strike the beach with greater frequency.

49)The attracting and repelling forces of magnets are used in countless objects, from refrigerator doors to maglev trains. Refrigerator doors use the attraction of magnets to stay closed, while maglev trains use magnetic repulsion to hover above rails. The center magnet in the picture is hovering between two magnets, making it appear to float. Which best explains how the center magnet is able to hover between two other magnets?

A) / The magnets are stacked so that similar poles are facing one another.
B) / The opposite poles of each magnet are facing each other, so they repel.
C) / The middle magnet is repelling the top magnet while attracting the bottom.
D) / The middle magnet is attracted to the top magnet, but held down by gravity.

50)In the military, night vision goggles are used to pull off secret missions into areas that are very dangerous. For this reason, the soldiers try to infiltrate at night so they can't be seen. Thermal-imaging devices are often used as well to locate people on these highly secretive missions. What type of electromagnetic radiation is being utilized?

A) / radio waves
B) / gamma rays
C) / ultraviolet rays
D) / infrared waves