Obtain the formula for the maximum safe speed $(v_{max})$ of a vehicle on a level curved road.
In figure $(a)$ vehicle is shown moving on a horizontal curved road. The mass of vehicle be $m$ and the radius be $\mathrm{R}$.
Figure $(b)$ shows the vehicle moving on a circular track. The vehicle experiences three kinds of force :
$(1)$ Weight in downward direction.
$(2)$ Normal Reaction force in opposite direction ' $w$ '. i.e., $\mathrm{N}=m g \ldots$ (1)
$(3)$ Friction force $f=\mu \mathrm{N}$ along the surface of road.
The friction between the tyre and the road surface provides the necessary centripetal force.
$\therefore \mathrm{F}_{\mathrm{C}}=f$
$\therefore \frac{m v^{2}}{\mathrm{R}}=f \quad \cdots(2) \quad\left[\because \mathrm{F}_{\mathrm{C}}=\frac{m v^{2}}{\mathrm{R}}\right]$
In order to move safely on this road, $\frac{m v^{2}}{\mathrm{R}}$ force is required and it should be equal to maximum frictional force.
$\left(f_{s}\right)_{\max } &=\mu_{s} \mathrm{~N}$
$=\mu_{s} m g[\because \mathrm{N}=m g]$
Where $\mu_{s}$ is the coefficient of static friction between the tyres of vehicle and the road.
A modern grand-prix racing car of mass $m$ is travelling on a flat track in a circular arc of radius $R$ with a speed $v$. If the coefficient of static friction between the tyres and the track is $\mu_{s},$ then the magnitude of negative lift $F_{L}$ acting downwards on the car is
(Assume forces on the four tyres are identical and $g =$ acceleration due to gravity)
Defined a vehicle can be parked on a slope.
A disc revolves with a speed of $33 \frac{1}{3}\; rev/min$, and has a radius of $15 \;cm .$ Two coins are placed at $4\; cm$ and $14 \;cm$ away from the centre of the record. If the co-efficient of friction between the coins and the record is $0.15,$ which of the coins will revolve with the record?
Four identical point masses $'m'$ joined by light string of length $'l'$ arrange such that they form square frame. Centre of table is coincide with centre of arrangment. If arrangement rotate with constant angular velocity $'\omega '$ , find out tension in each string
A plank is resting on a horizontal ground in the northern hemisphere of the earth at a $45^{\circ}$ latitude. Let the angular speed of the earth be $\omega$ and its radius $r_e$. The magnitude of the frictional force on the plank will be