# Problem 911 | Combined Axial and Bending

# Length of Parabolic Sag Curve with Given Change in Grade Per Station

**Problem**

A grade of -5% is followed by a grade of 1%, the grades intersecting at the vertex (Sta. 10 + 060). The change of grade is restricted to 0.4% in 20 m. Compute the length of the vertical parabolic sag curve in meters.

A. 360 m | C. 300 m |

B. 320 m | D. 340 m |

# Cross-Sectional Dimensions of Steel Rod to Elongate 1-mm when Subjected to 8,000 kg of Tension Force

**Problem**

A tensile load of 8000 kg elongates a 1-m long square rod by 1 mm. Steel modulus of elasticity is 2 × 10^{6} kg/cm^{2}. What is the dimension of a side of the rod?

A. 5 cm | C. 2 cm |

B. 1 cm | D. 4 cm |

# The Distance the Particle Travels with Given Position Function x(t) = t^4 - 8t^2

# Compound Curves: Finding the Stationing of PCC with Given Stationing of PC

**Problems**

A compound curve has the following characteristics:

I_{1} = 24° |
D_{1} = 6° |

I_{2} = 36° |
D_{2} = 4° |

Stationing of P.C. = km 10 + 420 |

Compute the stationing of *P.C.C.*

A. km 10 + 560 | C. km 10 + 520 |

B. km 10 + 540 | D. km 10 + 500 |

# For Sn = 3^(2n - 1) + b; Find the Quotient a9 / a7

**Problem**

The sum of the first *n* terms of a series is 3^(2*n* - 1) + *b*. What is the quotient of the 9^{th} and the 7^{th} term?

A. 81 | C. 83 |

B. 82 | D. 84 |

# Y-component of Vector A if Vectors A and B are Orthogonal

**Problem**

Compute the value of *b* if **A** and **B** are orthogonal.

$${\bf A} = 2{\bf i} + b{\bf j} + {\bf k}$$

$${\bf B} = 4{\bf i} - 2{\bf j} - 2{\bf k}$$

A. 6 | C. 4 |

B. 5 | D. 3 |

# General Term of Arithmetic Sequence that Models the Potential Annual Salaries

**Problem**

A job posted at jobstreet.com offered a starting salary of \$40,000 per year and guaranteeing a raise of \$1600 per year for the rest of 5 years. Write the general term for the arithmetic sequence that models potential annual salaries.

*a*= 38,400 + 1600

_{n}*n*

B.

*a*= 33,400 + 2600

_{n}*n*

C.

*a*= 36,400 + 1400

_{n}*n*

D.

*a*= 34,400 +1800

_{n}*n*

# Weight of Copper and Tin to Produce an Alloy of 30% Copper and 10% of Tin

**Problem**

A given alloy contains 20% copper and 5% tin. How many pounds of copper and of tin must be melted with 100 lb of the given alloy to produce another alloy analyzing 30% copper and 10% tin? All percentages are by weight.

B. 17.5 lb copper and 7.5 lb tin

C. 19.5 lb copper and 5.5 lb tin

D. 18.5 lb copper and 6.5 lb tin