1 ) Two springs of spring constant k1 and k2 at joined in series . Then effective spring constant of combination is . . . . . . . . . . . . ?
Solution
: -
Formulas
: -
for parallel : -
ke = k1 + k2 + .......... ,
for series : - 1/ke = 1/k1 + 1/k2 + ....... ,
So , as by question ;
1/ke = 1/k1 + 1/k2 ,
so ,
ke = (k1 x k2) / (k1 + k2) , Answer .
2 )
If earth is treated as a sphere of radius R and mass M , its angular momentum
about axis of rotation with period T is . . . . . . . . . . ?
Solution : -
3 )
Moment of inertia depends on . . . . . . . . . . . . . : -
A ) mass of body , B
) axis of rotation ,
C ) shapes and sizes , D
) All of these ,
Correct
Answer : - D ) All of these ,
4 )
Product of uncertainty in positron and momentum is equals to . . . . . . . . .
. . . . . ,
A ) kinetic energy , B
) planks constant ,
C ) angular momentum , D
) None of these ,
Correct
Answer : - B ) planks constant ,
Because (∆P)
x (∆X) =
h ,
And
uncertainty in energy and time is also equals to planks constant ,
(∆E) x
(∆t) = h ,
5 )
In the absence of external torques , the system total angular momentum will be
: -
A ) conserved , B
) non - conserved ,
C ) may A or B , D
) None of these ,
Correct
Answer : - A ) conserved ,
6 ) A
couple produces . . . . . . . . . . . . . . . ( only rotational motion ) in the
body .
A
couple consists of two equal and opposite forces acting at a separation , so
that net force becomes zero .
Now go to online quiz section and Physics Quiz 9 is uploaded related to these mcqs , so check your preparation by this link : -
