Frame of Reference

A circular disc with a groove along its diameter is placed horizontally on a rough surface. A block of mass $1 \mathrm{kg}$ is placed as shown. The co-efficient of friction between the block and all surfaces of groove and horizontal surface in contact is $\mu =\frac{2}{5}.$ The disc has an acceleration of $25 {\mathrm{ms}}^{-2}$ towards left. Find the acceleration of the block with respect to disc. Given, $\cos \theta =\frac{4}{5}, \sin \theta =\frac{3}{5}$

Two blocks of mass $m_1=10 \mathrm{kg}$ and $m_2=5 \mathrm{kg}$, connected to each other by a massless inextensible string of length $0.3 \mathrm{m}$ are placed along a diameter of a turn table. The coefficient of friction between the table and $m_1$ is $0.5$ while there is no friction between $m_2$ and the table. The table is rotating with an angular velocity of $10 {\mathrm{rads}}^{-1}$ about a vertical axis passing through its centre $O$. The masses are placed along the diameter of the table on either side of the centre $O$ such that the mass $m_1$ is at a distance of $0.124 \mathrm{m}$ from $O$. The masses are observed to be at rest with respect to an observer on the turn table. Calculate the frictional force on $m_1$.

A stone is thrown vertically up from floor of a lift with a velocity $20 \mathrm{m} {\mathrm{s}}^{-1}$ relative to the lift and the time of flight is found to be$2$seconds (a) Find the magnitude of acceleration with which the lift is moving? (b) Write down the direction of acceleration with which the lift is moving?

A balloon of mass$M$ is descending  with constant acceleration $\frac{g}{3}$ when mass $m$ is released from the balloon, it starts with same acceleration $\frac{g}{3}$. What is the value of $m$

 For a car moving on the road it will be considered to be at rest with respect to the
 

In a non-inertial frame the second law of motion is written as

A bock is sliding along smooth incline as shown in figure. If the acceleration of chamber is a as shown in the figure. The time required to cover a distance
$L$ along the incline is:

The weight of a body is $5 \mathrm{kgwt}$or$5 \mathrm{kgf}$ when placed at rest, if it is now placed in a lift (a) moving up with acceleration $4.9 \mathrm{m} {\mathrm{s}}^{-2}$ (b) moving down with acceleration $4.9 \mathrm{m} {\mathrm{s}}^{-2}$ (c) moving down with acceleration $9.8 \mathrm{m} {\mathrm{s}}^{-2}$ then what will be the weight of that body in absolute S.I. units for all the cases?

A man of mass $m$ is standing on the platform of mass$3m$ is kept on a smooth horizontal plane. If length of platform is $12.0 \mathrm{m}$ and the man moves from one end to other end of platform, then displacement of man in ground frame, is
 

Calculate the length contraction and orientation of a rod of length $5 \mathrm{m}$ in a frame of reference which is moving with a velocity $0.6 \mathrm{c}$ in a direction making on angle $30°$ with the rod. 

A block of mass $1 \mathrm{kg}$ is placed on a rough wedge which is fixed on an elevator moving upward with constant velocity $2 \mathrm{m} {\mathrm{s}}^{-1}$. The block is at rest w.r.t. wedge. Net reaction force on the block is $\left(\mathrm{g}=10 \mathrm{m} {\mathrm{s}}^{-2}\right)$

The resultant force acting on a moving body is zero, then

If $m$ does not slide on wedge, find reading of weighing machine

A block shown in the figure is kept on a table which is moving up with acceleration $2 \mathrm{m} {\mathrm{s}}^{-2}$. Find force $F$ at which the block tends to move.

A block of mass $m=10\mathrm{kg}$ hangs from ceiling of an elevator, through a string, as shown in the figure. If the lift moves up with a constant speed $10 \mathrm{m} {\mathrm{s}}^{-1}$, then the work done by tension in string on mass $m$, in $2 \mathrm{s}$ w.r.t. an observer on the ground will be $\left[g=10 \mathrm{m} {\mathrm{s}}^{-2}\right]$

A car moves horizontally with a constant acceleration of $3 \mathrm{m} {\mathrm{s}}^{-2}$. A ball is suspended by a string from the ceiling of the car. The ball does not swing, being at rest with respect to the car. What angle does the string make with the vertical?

What is Coriolis force?