Question: In actual machines, mechanical advantage is __________ velocity ratio.
[A].equal to
less than
greater than
[A].
[B].
[C].
Answer: Option B
Explanation:
No answer description available for this question.
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In ideal machines, mechanical advantage is __________ velocity ratio.
Question: In ideal machines, mechanical advantage is __________ velocity ratio.
[A].equal to
less than
greater than
[A].
[B].
[C].
Answer: Option A
Explanation:
No answer description available for this question.
If the efficiency of a lifting machine is kept constant, its velocity ratio is __________ propotional to its mechanical advantage.
Question: If the efficiency of a lifting machine is kept constant, its velocity ratio is __________ propotional to its mechanical advantage.
[A].directly
inversely
[A].
[B].
Answer: Option A
Explanation:
No answer description available for this question.
An ideal machine is one whose efficiency is
Question: An ideal machine is one whose efficiency is
[A].between 60 and 70 %
between 70 and 80%
between 80 and 90%
100%
[A].
[B].
[C].
[D].
Answer: Option D
Explanation:
No answer description available for this question.
The angle between two forces when the resultant is maximum and minimum respectively are
Question: The angle between two forces when the resultant is maximum and minimum respectively are
[A].0° and 180°
180° and 0°
90° and 180°
90° and 0°
[A].
[B].
[C].
[D].
Answer: Option A
Explanation:
No answer description available for this question.
Efficiency of a screw jack is given by(where α = Helix angle, and φ = Angle of friction.)
Question: Efficiency of a screw jack is given by(where α = Helix angle, and φ = Angle of friction.)
[A].
[A].
[B].
[C].
[D].
Answer: Option B
Explanation:
No answer description available for this question.
In a screw jack, the effort required to lower the load is __________ the effort required to raise the same load.
Question: In a screw jack, the effort required to lower the load is __________ the effort required to raise the same load.
[A].less than
equal to
more than
[A].
[B].
[C].
Answer: Option A
Explanation:
No answer description available for this question.
In a screw jack, the effort required to lift the load is given by(where W = Load lifted, α = Helix angle, and φ = Angle of friction.)
Question: In a screw jack, the effort required to lift the load is given by(where W = Load lifted, α = Helix angle, and φ = Angle of friction.)
[A].P = W tan (α – φ)
P = W tan (α + φ)
P = W tan (φ – α)
P = W cos (α + φ)
[A].
[B].
[C].
[D].
Answer: Option B
Explanation:
No answer description available for this question.
A ladder is resting on a rough ground and leaning against a smooth vertical wall. The force of friction will act
Question: A ladder is resting on a rough ground and leaning against a smooth vertical wall. The force of friction will act
[A].downward at its upper end
upward at its upper end
zero at its upper end
perpendicular to the wall at its upper end
[A].
[B].
[C].
[D].
Answer: Option C
Explanation:
No answer description available for this question.
A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act
Question: A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act
[A].towards the wall at its upper and
away from the wall at its upper end
downward at its upper end
upward at its upper end
[A].
[B].
[C].
[D].
Answer: Option D
Explanation:
No answer description available for this question.