A block of wood resting on an inclined plane of angle $30^o$, just starts moving down. If the coefficient of friction is $0.2$, its velocity (in $ms^{-1}$) after $5\, seconds$ is : $(g = 10\, ms^{-2})$

A uniform rope of total length $l$ is at rest on a table with fraction $f$ of its length hanging (see figure). If the coefficient of friction between the table and the chain is $\mu$, then

A bullet of mass $20\, g$ travelling horizontally with a speed of $500 \,m/s$ passes  through a wooden block of mass $10.0 \,kg$ initially at rest on a surface. The bullet  emerges with a speed of $100\, m/s$ and the block slides $20 \,cm$ on the surface  before coming to rest, the coefficient of friction between the block and the surface. $(g = 10\, m/s^2)$

When two surfaces are coated with a lubricant, then they

A body of mass $4\, kg$ is at rest on a horizontal table. The coefficient of friction between  the body and the table is $0.2$ . A horizontal force of $6N$ is applied on the body.  The acceleration of the body is .......... $m/s^2$

A $1\,kg$ block is being pushed against a wall by a force $F = 75\,N$ as shown in the Figure. The coefficient of friction is $0.25.$ The magnitude of acceleration of the block is ........ $m/s^2$