Applied Mechanics (General Engineering) (SSC JE)

Total Questions: 50

11. Two unlike parallel forces are shown in the following figure : [BPSC AE (GEN. ENGG.) 14.10.2022 ]


The resultant R can be located by the relation

Correct Answer: (d) F₁ × d₁ = F₂ × d₂
Solution:


Rule of equilibrium–
∑H = 0
∑V = 0
∑M = 0
Taking moment about R
F₁ × d₁ - F₂ × d₂
F₁ × d₁ = F₂ × d₂

12. A circular disc rotating with constant angular speed of 5 rad/s, moves along a straight line. The mass and the radius of the disc are 10 kg and 1.0 m respectively. The total kinetic energy possessed by the disc will be [BPSC AE (GEN. ENGG.) 14.10.2022 ]

Correct Answer: (a) 187.5 N-m
Solution:

13. If the tension in the cable supporting the lift moving upwards is twice the tension when the lift in moving downwards, the acceleration of the lift is equal to [BPSC AE (GEN. ENGG.) 14.10.2022 ]

Correct Answer: (b) g/3
Solution:

Let acceleration of the lift while moving upward or downward 'a'.

14. A retarding force on a body does not [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (b) retard the motion of the body
Solution:

A retarding force on a body does not retard the motion of the body.
• A retarding force is simply the force that is applied in the opposite direction to the direction of motion and produces deceleration in a body or it produces negative acceleration.

15. The centre of gravity of a quadrant of a circle lies along its central radius at distance of [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (c) 0.4 R
Solution:


16. If two forces P and Q (P >Q) act on the same straight line but in opposite direction, their resultant is [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (d) P – Q
Solution:

Given,
P > Q
When force P and Q are opposite to each other. If it is in the direction then θ = 180°

17. If two forces of 3 kg. and 4 kg. act at right angles to each other, their resultant force will be equal to [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (c) 5 kg
Solution:

18. If two equal forces of magnitude P act an angle. Their resultant will be [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (d)
Solution:

19. The velocity of a moving body, is [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (a) vector quantity
Solution:

Velocity–It is a vector quantity which means we need both magnitude (speed and direction) to define velocity. The SI unit of it is meter per second.

20. Time required to stop a car moving with a velocity of 20 m/sec within a distance of 40 m, is [BPSC AE (GEN. ENGG.)-2006 ]

Correct Answer: (a) 4 sec
Solution:

 

Note–The commission has not accepted any option as correct.