# A vibrating system with viscous damping have Mass = 2.5 kg, spring constant = 3 N/mm and the amplitude decreases to 0.25 of the initial value after five consecutive cycles. The damping coefficient of the damper in the system will be

1.  5.65 N/m/s

2.  6.65 N/m/s

3.  7.65 N/m/s

4.  8.65 N/m/s

4

7.65 N/m/s

Explanation :
No Explanation available for this question

# The equation of the water column in a U-tube shown in the figure is

1.  ωn = √(g/l)

2.  ωn = √(2g/l)

3.  ωn = √(g/2l)

4.  ωn = √(l/g)

4

ωn = √(2g/l)

Explanation :
No Explanation available for this question

# The natural frequency of a vibrating system shown in the figure is equal to

1.

2.

3.

4.  None of these

4

Explanation :
No Explanation available for this question

# A refrigerator unit weighing 300 N is to be supported by three spring of stiffness of 10.26 kN/mm each. If the unit operators at 580 rpm, what should be the value of the spring constant k if only 10 % of the shaking force of the unit is to be transmitted to the supporting structure

1.  2.4 N/mm

2.  3.0 N/mm

3.  3.4 N/mm

4.  4.0 N/mm

4

3.4 N/mm

Explanation :
No Explanation available for this question

# A beam ABCD is simply supported at the ends A and D which are 6 m apart. At B, distant 2.4 m from A, a concentrated load of 50 kN is rigidly attached to the beam and at C, which is 4.5 m from A, a load of 40 kN is similarly fixed. The second moment of area of the cross-section of the beam is 1665 * 105 mm4. Find the approximate number of vibrations per second of the system if E = 2.0 * 105 n/mm2.

1.  3.2

2.  4.2

3.  5.2

4.  6.2

4

5.2

Explanation :
No Explanation available for this question

# An engine is mounted on a concrete block which is isolated from the floor, as shown in the figure. The unbalanced force of the engine at N rpm is given by 100 (N/1000)2 cos (2πNt/60) new tons. At 2000 rpm it is found that the force transmitted to the floor has amplitude of 400 new tons. What is the amplitude of the transmitted force at 2500 rpm when the damper is disconnected

1.  2.62 N

2.  284 N

3.  294 N

4.  312 N

4

294 N

Explanation :
No Explanation available for this question

# A truck weighing 150 kN and travelling at 2 m/s impacts with a buffer spring which compresses 1.25 cm per 10 kN. The maximum compression of the spring will be

1.  26.6 cm

2.  27.6 cm

3.  28.6 cm

4.  30.6 cm

4

27.6 cm

Explanation :
No Explanation available for this question

# With symbols having the usual meanings, the single degree of freedom system, mx + cx + kx = F sin ωt represents

1.  Free vibrations with damping

2.  Free vibrations without damping

3.  Forced vibrations with damping

4.  Forced vibrations without damping

4

Forced vibrations with damping

Explanation :
No Explanation available for this question

# In the two-rotor system shown in the figure, (I1 < I2), a node of vibration is situated

1.  Between I1 and I2 but nearer to I1

2.  Between I1 and I2 but nearer to I2

3.  Exactly in the middle of the shaft

4.  Nearer to I1 but outside

4

Nearer to I1 but outside

Explanation :
No Explanation available for this question

1.  N/2

2.  2N

3.  4N

4.  8N

4