# Machine Kinematics Mcqs

Q:

A) 45.5 | B) 46.8 |

C) 45.1 | D) 47.2 |

107

Q:

A) 1.5 | B) 1.75 |

C) 2 | D) 1,33 |

Answer & Explanation
Answer: B) 1.75

Explanation: R = mT/2 = 480mm

r = mt/2 = 180mm

Addendum radius of pinion = 190mm

Addendum radius of gear = 490mm

Using the relation for length of path of approach

We get path of approach = 27.3mm

Path of recess = 25mm

adding both we get total length of path of contact

= 52.3mm

Length of arc of contact = length of path of contact / cos?

Contact ratio = Length of arc of contact/Pc

=1.75.

Explanation: R = mT/2 = 480mm

r = mt/2 = 180mm

Addendum radius of pinion = 190mm

Addendum radius of gear = 490mm

Using the relation for length of path of approach

We get path of approach = 27.3mm

Path of recess = 25mm

adding both we get total length of path of contact

= 52.3mm

Length of arc of contact = length of path of contact / cos?

Contact ratio = Length of arc of contact/Pc

=1.75.

98

Q:

A) True | B) False |

Answer & Explanation
Answer: B) False

Explanation: Maximum sliding velocity is the sum of angular velocities and its product with the length of path of appraoch.

Vs = (?? + ??)x(length of path of approach).

Explanation: Maximum sliding velocity is the sum of angular velocities and its product with the length of path of appraoch.

Vs = (?? + ??)x(length of path of approach).

89

Q:

A) 52.333 | B) 55.66 |

C) 53.22 | D) 54.55 |

Answer & Explanation
Answer: B) 55.66

Explanation: R = mT/2 = 480mm

r = mt/2 = 180mm

Addendum radius of pinion = 190mm

Addendum radius of gear = 490mm

Using the relation for length of path of approach

We get path of approach = 27.3mm

Path of recess = 25mm

adding both we get total length of path of contact

= 52.3mm

Length of arc of contact = length of path of contact / cos?

= 55.66mm.

Explanation: R = mT/2 = 480mm

r = mt/2 = 180mm

Addendum radius of pinion = 190mm

Addendum radius of gear = 490mm

Using the relation for length of path of approach

We get path of approach = 27.3mm

Path of recess = 25mm

adding both we get total length of path of contact

= 52.3mm

Length of arc of contact = length of path of contact / cos?

= 55.66mm.

97

Q:

A) 52.3 | B) 55.4 |

C) 53.2 | D) 54.5 |

Answer & Explanation
Answer: A) 52.3

Explanation: R = mT/2 = 480mm

r = mt/2 = 180mm

Addendum radius of pinion = 190mm

Addendum radius of gear = 490mm

Using the relation for length of path of approach

We get path of approach = 27.3mm

Path of recess = 25mm

adding both we get total length of path of contact

= 52.3mm.

Explanation: R = mT/2 = 480mm

r = mt/2 = 180mm

Addendum radius of pinion = 190mm

Addendum radius of gear = 490mm

Using the relation for length of path of approach

We get path of approach = 27.3mm

Path of recess = 25mm

adding both we get total length of path of contact

= 52.3mm.

85

Q:

A) 6.12 | B) 6.51 |

C) 6.61 | D) 6.81 |

Answer & Explanation
Answer: A) 6.12

Explanation: Pc = ?m = 18.85mm

Arc of contact = 1.75xp = 33mm

Length of path of contact = cos?x Arc of contact

From another relation of length of path of contact we get

Ra = 126.12 mm

R = 120mm

Therefore addendum = 6.12mm.

Explanation: Pc = ?m = 18.85mm

Arc of contact = 1.75xp = 33mm

Length of path of contact = cos?x Arc of contact

From another relation of length of path of contact we get

Ra = 126.12 mm

R = 120mm

Therefore addendum = 6.12mm.

74

Q:

A) Sum of path of recess and path of approach | B) Difference of path of approach and path of recess |

C) Twice the arc of approach | D) Twice the path of recess |

Answer & Explanation
Answer: A) Sum of path of recess and path of approach

Explanation: The path of contact is given by the sum of Length of path of approach and length of path of recess. Numerically it is dependent on pitch radius, addendum radius and the sine of pressure angle.

Explanation: The path of contact is given by the sum of Length of path of approach and length of path of recess. Numerically it is dependent on pitch radius, addendum radius and the sine of pressure angle.

85

Q:

A) Sum of Arc of recess and Arc of approach | B) Difference of arc of approach and arc of recess |

C) Twice the arc of approach | D) Twice the arc of recess |

Answer & Explanation
Answer: A) Sum of Arc of recess and Arc of approach

Explanation: The arc of contact is given by the sum of Length of arc of approach and length of arc of recess. Numerically it is the ratio of length of path of contact and the cosine of the pressure angle.

Explanation: The arc of contact is given by the sum of Length of arc of approach and length of arc of recess. Numerically it is the ratio of length of path of contact and the cosine of the pressure angle.

110