MCQ
3461. Two forces are acting at an angle of 120°. The bigger force is 40N and the resultant is perpendicular to the smaller one. The smaller force is-
20N
40N
80N
none of this
3462. The process of finding out the resultant force is called -----of force.
Composition
Resolution
3463. An irregular body may have more than one centre of gravity.....
Yes
No
3464. The slope of a stress-strain curve in the elastic deformation region is-
elastic modulus
plastic modulus
poison's ratio
none of the above
3465. The center of gravity of a semi-circle lies at a distance of ----from its base measured along the vertical radius. 8r
3r/8
3r/4π
4r/3π
8r/3
3466. 1kg force is equal to-
7.8N
12N
8.91 N
9.81N
3467. The angles between two forces when the resultant is maximum & minimum respectively are-
0° & 180°
180° & 0°
90° & 180°
90° & 0°
3468. A force while acting on a body may-
Change its motion
Balance the force
Internal stress rise
All of this
3469. The center of gravity of a right circular solid cone is at a distance of---- from its base, measured along the vertical axis.
h/2
h/3
h/4
h/6
3470. The resultant of two equal force P making an angle θ, is given by-
2P sinθ/2
2P cosθ/2
2P tanθ/2
2P cot-θ/2
3471. The terms 'leverage' & 'mechanical advantage' of a compound lever have got same meaning-----
Right
Wrong
3472. The resultant of two forces P & Q is R. If Q is doubled, the new resultant is perpendicular to P. Then-
P=Q
Q=R
Q=2R
none of these
3473. The resultant of two force P & Q acting at an angle θ is-
√P^2+Q^2+2PQsinθ
√P^2+Q^2+2PQcosθ
√P^2+Q^2-2PQcosθ
3474. The center of gravity of a T-section 100mm x 150mm x 50mm from its bottom is-
50mm
75mm
87.5mm
125mm
3475. If the resultant of a number of forces acting on a body is 0. Then the body will be equilibrium........
Yes
No
3476. Whenever a material is loaded within elastic limit, stress is-strain. [BREB-15]
equal to
directly proportional to
inversely proportional to
None of these
3477. A smooth cylinder lying on its convex surface remains in- equilibrium.
stable
neutral
unstable
none of these
3478. An ideal machine is one whose efficiency is- [BREB-15]
between 60 and 70%
between 70 and 80%
between 80 and 90%
100%
3479. If the resultant of two force P & Q acting at an angle θ, makes an angle α with force P, then-
tanα = P sinθ / P+Q cosθ
tanα = P cosθ / P+Q cosθ
tanα = Q sinθ / P+Q cosθ
3480. The friction experienced by a body, when at rest, is known as- (BREB-15]
static friction
coefficient of friction
dynamic friction
limiting friction