Download App

Model Paper 8 — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsModel Paper 81 Mark
MCQ
The instantaneous angular position of a point on a rotating wheel is given by the equation $\theta(t)=2 t^3-6 t^2$. The torque on the wheel becomes zero at
  • A
    $t =0.25 s$
  • B
    $t =0.5 s$
  • C
    $t=2 s$
  • D
    $t=1 s$
✓

Answer

(d) $t=1 s$
$
\begin{aligned}
& \text { Explanation: } \theta(t)=2 t^3-6 t^2 \\
& \omega=\frac{d \theta}{d t}=6 t^2-12 t \\
& \alpha=\frac{d \omega}{d t}=12 t-12=0 \\
& \Rightarrow t=1 s
\end{aligned}
$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from Model Paper 8→Model Paper 8 — all question types→Physics STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

A bottle of sodawater is grasped by the neck and swing briskly in a vertical circle. Near which portion of the bottle do the bubbles collect
→
Two identical mass $m$ are connected to a massless string which is hung over two frictionless pulleys as shown in figure. If everything is at rest, what is the tension in the cord?
→
A box is placed on an inclined plane and has to be pushed down. The angle of inclination is
→
A steam boat goes across a lake and comes back : $(i)$ on a quiet day when the water is still and $(ii)$ on a rough day when there is a uniform current so as to help the journey onward and to impede the journey back. If the speed of the launch, on both days, was same, the time required for the complete journey on the rough day as compared to that on the quiet day, will be
→
An artificial earth satellite of mass $m$ is circling round the earth in an orbit of radius $R$. If the mass of the earth is $M,$ then the total energy of the satellite is:
→
A body $x$ with a momentum $p$ collides with another identical stationary body $y$ one dimensionally. During the collision $y$ gives an impulse $J$ to body $x$. Then coefficient of restitution is
→
The percentage errors in quantities $P, Q, R$  and $S$  are $0.5\%,\,1\%,\,3\%$  and  $1 .5\%$ respectively in the  measurement of a physical quantity $A\, = \,\frac{{{P^3}{Q^2}}}{{\sqrt {R}\,S }}$ . the maximum percentage error in the value of $A$  will be ........... $\%$
→
A $metre$ scale is suspended vertically from a horizontal axis passing through one end of it. Its time period would be ....... $\sec$
→
An increases in pressure required to decreases the $200$ litres volume of a liquid by $0.004\%$ in container is .......... $kPa$ (Bulk modulus of the liquid $= 2100\, MPa$)
→
If the metal bob of a simple pendulum is replaced by a wooden bob, then its time period will
→