Education Exams (Educ Gen Sci) – Page 3

#40. Because of biogeochemical cycling?
A Organisms eventually run out of needed elements, compounds and other form of matter.
B The Earth creates new chemicals that replace those that were used up by organisms.
C Nutrients are circulated throughout the biosphere.
D Human activity has no effects on elements, chemical compounds, and other forms of matter.
Answer: Nutrients are circulated throughout the biosphere.
#41. Which of the biogeochemical cycles can impact all of the others most directly?
A Carbon cycle
B Phosphorous cycle
C Hydrologic cycle
D Nitrogen cycle
Answer: Hydrologic cycle
#42. What human activity has added the most carbon in the atmosphere?
A Increasing soil erosion
B Mining fossil fuels
C Burning fossil fuels
D Cutting down the rain-forests
Answer: Burning fossil fuels
#43. Albert Einstein's Second Postulate of Special Relativity states that the speed of light ________.
A randomly changes depending upon its original light source
B can increase if the speed of light source increases
C is constant regardless of the speed of the observer or the light source
D can decrease if the speed of the observer decreases
Answer: is constant regardless of the speed of the observer or the light source
#44. A passenger train travels east at high speed. One passenger is located at the east side of one car, another is located at the west side of that car. In the train frame, these two passengers glance up at the same time. In the earth's frame ________.
A the passengers glance sideways
B the passenger at the west side glances up first
C the passenger at the east side glances up first
D they glance up simultaneously
Answer: the passenger at the west side glances up first
#45. Beniell travels at high speed from Earth to the star Alpha Centauri which is four years away. Which one is CORRECT in Beniell's frame?
A The clocks on earth and on Alpha Centauri are synchronized.
B The trip takes more time than it does in the earth's frame.
C Beniell travels to Alpha Centauri over a length that is shorter than four light years.
D Alpha Centauri travels to Beniell over a length that is shorter than four light years.
Answer: Alpha Centauri travels to Beniell over a length that is shorter than four light years.
#46. One clock is placed on top of a mountain and another clock is at the bottom of the mountain. Ignore the rotation of the earth. Which clock ticks more slowly?
A Cannot be determined.
B They tick at the same rate.
C The one on top of the mountain.
D The one at the bottom of the mountain.
Answer: The one at the bottom of the mountain.
#47. You are in a windowless spacecraft. What do you need to do to determine whether your space ship is moving at constant non-zero velocity, or is at rest, in an inertial frame of earth?
A Make very precise time measurements.
B Make very precise mass measurements.
C Nothing, because you cannot succeed no matter what you do.
D Make very precise length and time measurements.
Answer: Nothing, because you cannot succeed no matter what you do.
#48. According to the effects of length contraction, from the viewpoint of an observer stationary with respect to a body moving at a uniform speed relative to the observer, which one is CORRECT?
A The body is not now contracted but would contract if it were to accelerate.
B The time it takes for a clock incorporated in the body to tick contracts
C The body contracts along the direction of the motion.
D The body contracts in some direction traverse to the direction of its motion.
Answer: The body contracts along the direction of the motion.
#49. April and May are identical twins. One day, April embarked on a high speed space travel into a distant star. When he gets back home, who is older between the two?
A None of them because they are still of the same age
B Cannot be determined
C April
D May
Answer: May
#50. An accelerated frame is a non-inertial frame. Is this TRUE?
A Sometimes true, sometimes false
B False
C Not enough information given
D True
Answer: True
#51. Which of the following statements is TRUE about the speed of light?
A The speed of light has a value that depends on the observer's frame of reference.
B The speed of light is constant in an inertial frame of reference.
C The speed of light has the same value for observers in all reference frames.
D The speed of light is slower in a moving frame of reference.
Answer: The speed of light is constant in an inertial frame of reference.
#52. A person is riding a moped that is traveling at 20 m/s. What is the speed of the ball if the moped rider throws a ball forward at 4 m/s while riding the moped?
A 20 m/s
B 16 m/s
C 24 m/s
D 80 m/s
Answer: 24 m/s
#53. As you observe a fish inside an aquarium, the fish appears to be bigger when underwater. When observed through the side, the fish seems closer than if you observe over the top. When you look through the corner, it appears to be that there are two fishes. What explains this observation?
A Reflection
B Refraction
C Interference
D Diffraction
Answer: Refraction
#54. What is the phenomenon by which the incident light falling on a surface is back into the same medium?
A Polarization
B Absorption
C Reflection
D Refraction
Answer: Reflection
#55. Which property is responsible for alternating light and dark bonds when light passes through two or more narrow slits?
A Refraction
B Diffraction
C Interference
D Polarization
Answer: Interference
#56. What happens when a light wave enters into a medium of different optical density?
A Its speed, frequency and wavelength change.
B Its frequency and wavelength change.
C Its speed and frequency change.
D Its speed and wavelength change.
Answer: Its speed and wavelength change.
#57. A ray of light in air is incident on an air-to-glass boundary at an angle of 36 degrees with the normal. If the index of refraction of the glass is 1.65, what is the angle of the refracted ray within the glass with respect to the normal?
A 18 degrees
B 30 degrees
C 46 degrees
D 56 degrees
Answer: 18 degrees
#58. If the critical angle for internal reflection inside a certain transparent material is found 48 degrees, what is the index of refraction of the material? (air is outside the material).
A 1.53
B 1.48
C 0.74
D 1.35
Answer: 1.35
#59. According to the law of reflection, from what angle is light coming after it is reflected from a mirror?
A The same angle as the incident ray as measured from the surface of the mirror.
B Some light comes directly from the object and some passes through the mirror.
C The same angle as the incident ray as measured from the normal to the mirror.
D Cannot be determined.
Answer: The same angle as the incident ray as measured from the normal to the mirror.