Download App

Rotational Mechanics — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsRotational Mechanics2 Marks
Question
A body rotates about a fixed axis with an angular acceleration of one radian/ second/ second. Through what angle does it rotate during the time in which its angular velocity increases from 5rad/s to 15rad/s.
✓

Answer

$\alpha=1\text{rad/s}^2,\ \omega_0=5\text{rad/s};\ \omega=15\text{rad/s}$

$\therefore\text{w}=\text{w}_0+\alpha\text{t}$

$\Rightarrow\text{t}=\frac{(\omega-\omega_0)}{\alpha}=\frac{(15-5)}{1}=10\text{sec}$

Also, $\theta=\omega_0\text{t}+\frac{1}{2}\alpha\text{t}^2$

$=5\times10+\frac{1}{2}\times1\times100=100\text{rad}$

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 "Short Answer Type Questions [2M]" from Rotational Mechanics→Rotational Mechanics — all question types→Physics STD 12 Science question papers→Bihar Board STD 12 Science question papers→Bihar Board question paper generator→

Similar questions

Can we conclude from the interference phenomenon whether light is a transverse wave or a longitudinal wave?
→
What is cyclotron ? State its two limitations.
→
What is resistivity ? On What factors does it depend and write its unit and dimensional formula.
→
A ball of superconducting material is dipped in liquid nitrogen and placed near a bar magnet.
i. In which direction will it move?
ii. What will be the direction of its magnetic moment?
→
Answer the following questions: Magnifying power of a simple microscope is inversely proportional to the focal length of the lens. What then stops us from using a convex lens of smaller and smaller focal length and achieving greater and greater magnifying power?
→
The frequency of incident radiation $v$ in a photo-electric cell is greater than threshold frequency $v_0$. If frequency $v$ is increased, then how stopping potential will vary keeping other factors constant?
→
One person says that the potential energy of a particular book kept in an almirah is 20J and the other says it is 30J. Is one of them necessarily wrong?
→
A particle starting from rest moves with constant acceleration. If it takes 5.0s to reach the speed 18.0km/h find:
  1. The average velocity during this period.
  2. The distance travelled by the particle during this period.
→
Two conducting spheres of radii R1 and R2 are kept widely separated from each other. What are their individual capacitances? If the spheres are connected by a metal wire, what will be the capacitance of the combination? Think in terms of series-parallel connections.
→
A capacitor of capacitance 'C' is being charged by connecting it across a dc source along with an ammeter.Will the ammeter show a momentary deflection during the process of charging? If so, how would you explain this momentary deflection and the resulting continuity of current in the circuit? Write the expression for the current inside the capacitor.
→