System of Particles and Rotational Motion Test

Result

System of Particles and Rotational Motion Test - 4

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

A _______ is a body with a perfectly definite and unchanging shape.

A
point body

B
rigid body

C
extended body

D
Both B and C

Solution

A rigid body, also known as extended body is a body with a perfectly definite and unchanging shape. The distances between different pairs of such a body do not change. A real body deform under the influence of forces. But in many situations the deformations are negligible.
Question 2
1 / -0

Let A be a unit vector along the axis of rotation of a purely rotating body and B be a unit vector along the velocity of a particle P of the body away from the axis. The value of (A.B) is

A
1

B
-1

C
0

D
None of these.

Solution

In rotation of a rigid body about a fixed axis, every particle of the body moves in a circle, which lies in a plane perpendicular to the axis and has its center on the axis.

Dot product is defined as,

A.B = AB cos θ

Since the angle between the vector A and B is 90°.

Therefore, the dot product of A and B vectors will be zero as,

A.B = AB cos 0° = 0
Question 3
1 / -0

The center of mass of any irregular shape is defined as;

A
the position where the weighted position vectors of all the parts of a system sum up to zero.

B
the position where the mass of the entire body is assumed to be concentrated.

C
the position where the weight of the body is the maximum

D
Both A and B

Solution

The center of mass of any irregular shape is the weighted position vectors of all the parts of the system sum up to zero. And it is considered to be a hypothetical point where the mass of the entire body is assumed to be concentrated.
Question 4
1 / -0

The axis of rotation of a purely rotating body

A
may pass through a particle of the body

B
may pass through the center of mass

C
must pass through center of the body

D
Both A and B

Solution

It is not necessary that the axis of rotation of a purely rotating body should pass through a particle of the body or the center of mass. The axis of rotation may lie outside.