Class 11th

Calculate the maximum acceleration of a moving car so that a body lying on the floor of the car remains stationary. The coefficient of static friction between the body and the floor is $0.15\left(\mathrm{g}=10{\mathrm{m}\mathrm{s}}^{-2}\right)$ .

A horizontal bridge is built across a river. A student standing on the bridge throws a small ball vertically upwards with a velocity $4{\mathrm{m}\mathrm{s}}^{-1}$ . The ball strikes the water surface after $4\mathrm{s}$ . The height of bridge above water surface is (Take $\mathrm{g}=$ $10{\mathrm{m}\mathrm{s}}^{-2}$  ):

Match List- I with List-II

List -I
(a) Li
(b) Na
(c) KOH
(d) Cs

List-II
(i) absorbent for carbon dioxide
(ii) electrochemical cells
(iii) coolant in fast breeder reactors
(iv) photoelectric cell

Choose the correct answer from the options given below:

The IUPAC name of an element with atomic number 119 is:

Identify the incorrect statement from the following

The ratio of the radius of gyration of a thin uniform disc about an axis passing through its centre and normal to its plane to the radius of gyration of the disc about its diameter is :

An electric lift with a maximum load of 2000Kg (lift + passenger) is moving up with a constant speed $1.5{\mathrm{m}\mathrm{s}}^{-1}$ ${}^{}$ . The frictional force opposing the motion is 2000N${}^{}$ . The minimum power delivered by the motor to lift in watts is : $\left(\mathrm{g}=10{\mathrm{m}\mathrm{s}}^{-2}\right)$

Two objects of mass $10\mathrm{k}\mathrm{g}$ and $20\mathrm{k}\mathrm{g}$ respectively are connected to the two ends of a rigid rod of length 10 $\mathrm{m}$ with negligible mass. The distance of the centre of mass of the system from the $10\mathrm{k}\mathrm{g}$  mass is :

If a soap bubble expands, the pressure inside the bubble :

Why are the graphs of rotational motion mostly similar to the ones in linear motion?