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11.

The resultant of two equal forces P making an angle ?, is given by

A.	2 P sin ?/2	B.	2 P cos ? / 2
C.	2 P tan ?/2	D.	2 P cot ?/2

12.

The angle between two forces when the resultant is maximum and minimum respectively are

A.	0? and 180?	B.	180? and 0?
C.	90? and 180?	D.	90? and 0?

13.

If the resultant of two equal forces has the same magnitude as either of the forces, then angle between the two forces is

A.	30?	B.	60?
C.	90?	D.	120?

14.

The resultant of the two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P. Then

A.	P = Q	B.	Q = R
C.	Q = 2R	D.	none of these

15.

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

A.	20N	B.	40N
C.	40N	D.	none of these

16.

The terms 'leverage' and 'mechanical advantage' of a compound lever have got the same meaning.

Right

Wrong

17.

A number of forces acting at a point will be in equilibrium, if

A.	all the forces are equally inclined	B.	sum of all the forces is zero
C.	sum of resolved parts in the vertical direction is zero (i.e. ?V = 0)	D.	sum of resolved parts in the horizontal direction is zero (i.e. ?H = 0)

18.

If a number of forces are acting at a point, their resultant will be inclined at an angle ? with the horizontal, such that

A.	tan ? = ?H / ?V	B.	tan ? = ?V / ?H
C.	tan ? = ?V x ?H

19.

The triangle law of forces states that if two forces acting simultaneously on a particle, be represented in magnitude and direction by the two sides of a triangle taken in order, then their resultant may be represented in mangnitude and direction by the third side of of a triangle, taken in opposite order.

TRUE

FALSE

20.

The polygon law of forces states that if a number of forces, acting simultaneously on a particle, be represented in magnitude and direction by the sides a polygon taken in order, then their resultant is represented in magnitude and direction by the closing side of the polygon, taken in opposite direction.

Correct

Incorrect