Lakshya Education MCQs

Question: The efficiency of a screw jack is maximum, when (where α = helix angle, and φ = angle of friction.)
Options:
A. α = 45° + φ/2
B. α = 45° - φ/2
C. α = 90° + φ
D. α = 90° - φ
Answer: Option B

Submit Answer & Explaination

Earn Reward Points by submitting Detailed Explaination for this Question

More Questions on This Topic :

Question 1. The overturning of a vehicle on a level circular path can be avoided if the velocity of vehicle is __________ √(gra/h)
  1.     Less than
  2.     Greater than
  3.     Equal to
  4.     None of these
Answer: Option A
Question 2. Efficiency of a screw jack is given by (where α = helix angle, and φ = angle of friction.)
  1.     tan(α + φ)/tanα
  2.     tanα/tan (α + φ)
  3.     tan(α - φ)/tanα
  4.     None of these
Answer: Option B
Question 3. Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its c.g. and parallel to the base, is
  1.     bh3/4
  2.     bh3/8
  3.     bh3/12
  4.     bh3/36
Answer: Option D
Question 4. Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its c.g. and parallel to the base, is
  1.     bh3/4
  2.     bh3/8
  3.     bh3/12
  4.     bh3/36
Answer: Option D
Question 5. The overturning of a vehicle on a level circular path can be avoided if the velocity of vehicle is __________ √(gra/h)
  1.     Less than
  2.     Greater than
  3.     Equal to
  4.     None of these
Answer: Option A
Question 6. Efficiency of a screw jack is given by (where α = helix angle, and φ = angle of friction.)
  1.     tan(α + φ)/tanα
  2.     tanα/tan (α + φ)
  3.     tan(α - φ)/tanα
  4.     None of these
Answer: Option B

Check all Questions in this Topic : Click HERE