Two blocks of masses $m_1$ and $m_2$ are connected by a massless string passing over a smooth pulley. The coefficient of kinetic friction between $m_1$ and the horizontal surface is $\mu_k$. If $m_2$ is descending with a constant acceleration $a$, what is the tension in the string?

An object at rest in space suddenly explodes into three parts of same mass. The momentum of the two parts are $2p\hat i\,and\,p\hat j$. The momentum of the third part

A 5 kg stationary bomb is exploded in three parts having mass $1:1:3$ respectively. Parts having same mass move in perpendicular directions with velocity 39 $\;{\rm{m}}{{\rm{s}}^{ - 1}}$, then the velocity of bigger part will be

A block of mass 2 kg is placed on a rough horizontal surface with coefficient of static friction μs = 0.5 and coefficient of kinetic friction μk = 0.4. If a horizontal force F is applied to the block, which gradually increases from 0 N, at what value of F will the block experience maximum static friction force?

A block of mass 2 kg is placed on a rough horizontal surface with coefficient of static friction 0.5 and kinetic friction 0.4. If a horizontal force of 8 N is applied to the block, what will be the acceleration of the block?

1 kg body explodes into three fragments. The ratio of their masses is $1:1:3$. The fragments of same mass move perpendicular to each other with speeds $\;30{\rm{m}}{{\rm{s}}^{ - 1}}$, while the heavier part remains in the initial direction. The speed of heavier part is

A bomb of mass 9 kg explodes into 2 pieces of mass 3kg and 6kg. The velocity of mass 3kg is 1.6 m/s, the K.E. of mass 6kg is

A particle moves in a circle with a uniform speed. When it goes from a point A to a diametrically opposite point B, the momentum of the particle changes by ${{\bf{\vec p}}_A} - {{\bf{\vec p}}_B} = 2{\rm{\;kg\;m}}{{\rm{s}}^{ - 1}}\left( {\hat j} \right)$ and the centripetal fore acting on it changes by ${{\bf{\vec F}}_A} - {{\bf{\vec F}}_B} = 8\,N\left( {\hat i} \right)$ where $\hat i\,and\,\hat j$ are unit vectors along X and Y axes respectively. The angular velocity of the particle is

Rolling friction is generally _______ than sliding friction.

A bomb of mass 3.0 kg explodes in air into two pieces of masses 2.0 kg and 1.0 kg .The smaller mass goes at a speed of $80{\rm{m}}{{\rm{s}}^{ - 1}}$.The total energy imparted to the two fragments is

Assertion: The coefficient of kinetic friction is generally less than the coefficient of static friction.

Reason: Kinetic friction acts when surfaces are in relative motion.