The centre of gravity of a plane lamina will not be at its geometrical centre if it is a a.Square b.Equilateral triangle c.Circle d.Rectangle e.Right angled triangle

1 Answer

Answer :

e. Right angled triangle

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Description : The C.G. of a plane lamina will not be at its geometrical centre in the case of a  (A) Right angled triangle  (B) Equilateral triangle  (C) Square  (D) Circle

Last Answer : (A) Right angled triangle 

Description : The centre of percussions is a.The point of application of the resultant of all the forces tending to cause a body to rotate about a central axis b.The point of application of the resultant ... .The point in a body about which it can rotate horizontally and oscillates under the influence of gravity

Last Answer : a. The point of application of the resultant of all the forces tending to cause a body to rotate about a central axis

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Last Answer : (b) \(rac{q^2}{4}\) (2√3 + 1).AC = q, ∠ABC = 90º ⇒ q = \(\sqrt{AB^2+BC^2}\)⇒ q = \(\sqrt{2x^2}\)⇒ q2 = 2x2 ⇒ \(x\) = \(rac{q}{\sqrt2}\)∴ Area of the re-entrant hexagon = Sum of areas of (ΔABC + ΔADC ... (rac{\sqrt3}{4}\)q2 + \(rac{\sqrt3}{8}\)q2 + \(rac{\sqrt3q^2}{8}\) = \(rac{q^2}{4}\) (2√3 + 1).

Description : Name the type of triangle formed. (a) Right angled (b) Equilateral (c) Isosceles (d) Scalene

Last Answer : (d) Scalene

Description : A imaginary planet has half the mass and half the radius of the earth. The acceleration of gravity at its surface would be a.9.8 m/s2 b.107 dynes c.4.9 m/s2 d.19.6 m/s2 e.2.45 m/s2

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Description : A point moves in such a manner that its distance from a fixed point is equal to its distance from a fixed line multiplied by a constant greater than one. The locus of the path traced by the point will be a a.Cycloid b.Hyperbola c.Circle d.Involute e.Ellipsc

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Description : The statement --- if forces acting on a point can be represented in magnitude and direction by the sides of a polygon taken in order then their resultant will be represented in magnitude and direction by the closing ... 's law of forces c.Law of polygon of forces d.D'Alembert's rule e.Lami's theorem

Last Answer : c. Law of polygon of forces

Description : The statement ---- if three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two ---- is known as a.Law of polygon of forces b.D'Alembert's principle c.Newtons law of forces d.Lami's theorem e.Law of triangle of forces

Last Answer : d. Lami's theorem

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Last Answer : d. accepts a heavy bag from one of his friends standing near by and holds it in his hand

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