PHYS*1070

INTRODUCTORY PHYSICS FOR THE LIFE SCIENCES I

SAMPLE FINAL EXAMINATION 3

N O T E: NOT ALL QUESTIONS MAY BE APPLICABLE IN CURRENT SEMESTER;

CLICK ON CORRECT ANSWER FOR SOLUTION

1. A travelling wave is given by the expression y = -15sin(12t+6x).
What are the correct values for the amplitude A, wavelength l
, angular frequency w , and period T?

A) amplitude = 15, wavelength = p/3,
w = 12, T= p /6

B) amplitude = -15, wavelength = 6, w = 12,
T = 1/12

C) amplitude = 15, wavelength = p /6, w
= 6, T = p /6

D) amplitude = -15, wavelength = p /3, w
= 6, T = 1/6

E) amplitude = 15, wavelength = p /3, w
= 12, T = 3/p

2. A porpoise sends an echo locating pulse (60 kHz) as it tracks the
path of a shark. The power associated with the pulse is 3.0 x 10^{-5}
watts. The intensity of the pulse at the position of the shark is 1.5 x
10^{-5} watts/m^{2}. What is the displacement amplitude
of the water molecules adjacent to the shark?

A) 1.2 x 10^{-11} m

B) 1.7 x 10^{-10} m

C) 2.S x 10^{-11} m

D) 3.8 x 10^{-10} m

E) 5.2 x 10^{-11} m

3. A beat frequency of 17 Hz is observed when the fundamental mode of
two hollow tubes is excited. The tubes differ in length but have similar
construction with an open end and one closed end. The shorter tube length
is 80 cm. What is the length of the longer tube?

A) 85 cm

B) 90 cm

C) 95 cm

D) 100 cm

E) 105 cm

4. The sound intensity of a train whistle is 1.0 x 10^{-3} watts/m^{2}
at a distance of 100 m. If the whistle sounds for 2 seconds and the frequency
of the sound is 500 Hz, what is the power and energy emitted by the train's
whistle?

A) 126 W, 63 J

B) 126 W, 252 J

C) 8.0 x 10^{-9} W, 4 x 10^{-2} J

D) 8.0 x 10^{-9} W, 1.6 x 10^{-8} J

E) 1.0 x 10^{-2} W, 20 x 10^{-2} J

5. The intensity level of a sound at a distance of 25 m from the source
is 80 db. What is the intensity level at a distance of 50 m?

A) 40 db

B) 20 db

C) 7 db

D) 77 db

E) 74 db

6. Which of the following diagrams correctly describes the refraction occurring as a light ray passes from air (n = 1) to glass (n = 1.50) to air again?

A)

C)

D)

E)

7. The end of a long glass rod 8 cm in diameter has a convex hemispherical
surface 4 cm in radius. The rod is placed in a liquid and an object is
placed 60 cm from the end of the rod and on its axis. This object is imaged
at a point 100 cm inside the rod. What is the refractive index of the liquid
if the refractive index of the rod is 1.5?

A) 1.15

B) 1.25

C) 1.35

D) 1.45

E) 1.55

8. An object 5 cm high is placed 10 cm in front of a thin lens with
a 15 cm focal length. What is the image position, height, and orientation?

A) q = 6.0 cm, height = 3 cm, orientation = erect

B) q = 30 cm, height = 15 cm, orientation = inverted

C) q = -30 cm, height = 3 cm, orientation = erect

D) q = 30 cm, height = 15 cm, orientation = inverted

E) q = -30 cm, height = 15 cm, orientation =
erect

9.An electron (m = 9.11X 10^{-31} kg) has a kinetic energy of
6.0 x 10^{-21} J. What is the energy of a photon which has the
same wavelength as that of the electron?

A) 9.9 x 10^{-18} J

B) 4.2 x 10^{-18} J

C) 1.0 x 10^{-17} J

D) 3.1 x 10^{-17} J

E) 1.0 x 10^{-16} J

10. The percent transmittance of a 1.0 cm. length of a solution is 85%.
What is the percent transmittance of a 3.0 cm length?

A) 85%

B) 61%

C) 55%

D) 41%

E) 45%

3-11. A standing wave is given by y = 4cos(5t)sin(6x). What is the standing
wave pattern at t = T/8?

A)

C)

D)

E)

12. See Exam.2 Question 11

13. See Exam 2 Question 12

14. A certain beam of light has a wavelength of 500 nm; 6 x 10^{18}
photons of this light are incident on an absorbing solution every second
and 7 x 10^{17} photons are transmitted. The concentration of the
solution is 3 x 10^{-4} moles dm^{-3} and the absorbing
path length is 2 cm. What is the extinction coefficient of the absorbing
species?

A) 982 dm^{3} mole^{-1} cm^{-1}

B) 1144 dm^{3} mole^{-1} cm^{-1}

C) 1555 dm^{3} mole^{-1} cm^{-1}

D) 2486 dm^{3} mole^{-1} cm^{-1}

E) 9423 dm^{3} mole^{-1} cm^{-1}

15. The graph of the probability distribution of a p electron on a covalently bonded molecule is given below.

Which one of the set of facts below is correct?

- | Value
of x |
Area under
the curve |
Value of Principle Quantum number, n | Graph of wave function |

A | 1/l | 3 | 1 | |

B | 2/l | 1 | 1 | |

C | 1/l | 3 | 3 | |

D | 2/l | 1 | 3 | |

E | 1/l | 1 | 3 |

16. Two equal charges +Q are separated by a distance d. Which of the
following statements is __not
__true?

A) The electric field half way between the two charges is zero and the
force on a charge +q at that position is also zero.

B) The electric field, at a point on the connecting line but nearer
to the left hand charge, is directed away from it; the force on a charge
+q at that place is in the same direction.

C) The electric field at a point on the connecting line but nearer to
the right hand charge is directed to the left; the force on a charge -q
at that place is directed to the right.

D) A point has been found on the connecting line where the force on
a charge +q is zero; this point is therefore half way between the two charges.

E) A point is found on the connecting line where
the force on a charge +q is zero; the force on a charge -q will be zero
at a different point.

17.

The circuit consists of four resistors with conductances given by
G G G G |

The voltage of the battery is 2.0 volts. Which set of values below is
correct?

- | I_{1} (amp) |
I_{2} (amp) |
I_{3} (amp) |
I_{4} (amp) |
I_{5} (amp) |

A | 2 | 2/3 | 2/3 | 2/3 | 2 |

B | 2 | 2/3 | 2/3 | 2/3 | 1 |

C | 2 | 1/3 | 1/3 | 1/3 | 2 |

D | 4 | 2/3 | 2/3 | 1/3 | 4 |

E | 4 | 4/3 | 4/3 | 4/3 | 4 |

18. The element Thorium decays radioactively to the element Protactinium. The decay is represented by the equation:

The particle missing in the box is:

A) an alpha particle

B) a beta particle

C) a proton

D) a neutron

E) a neutrino

19. A particular radio-isotope has a physical half life of 4 d. The
isotope, when administered to a human, is eliminated in the urine. Several
hours after injection of the isotope, the count rate from a 50 cc sample
of urine is 3000 counts per minute and 2 hours later it is lower by 20%
in a similar sample of 50 cc. What is the biological half life of the isotope?
.

A) 0.06 d

B) 0.19 d

C) 0.28 d

D) 0.35 d

E) 1.02 d

20. The count rate of a small radioactive source at a distance of 20
cm is 300 counts per minute. What will it be at a distance of 30 cm?

A) 927

B) 672

C) 453

D) 133

E) 87