A 2, kg stone at end of a string 1, m long is whirled in a vertical circle at a constant speed. spee

English

Gujarati

Hindi

5.Work, Energy, Power and Collision

medium

A $2\, kg$ stone at the end of a string $1\, m$ long is whirled in a vertical circle at a constant speed. The speed of the stone is $4\, ms^{-1}$. The tension in the string will be $52\, N$ when the stone is

A

At the top of the circle

B

Halfway down

C

At the bottom of the circle

D

None of these

Solution

By $\mathrm{T}=\mathrm{mg} \cos \theta+\frac{\mathrm{mv}^{2}}{\mathrm{r}}$

$52=2 \times 10 \cos \theta+\frac{2 \times(4)^{2}}{1}$

$\cos \theta=1 \Rightarrow \theta=0^{\circ}=$ at lowest point.

Standard 11

Physics

Share

Similar Questions

Concretemixture is made by mixing cement, stone and sand in a rotating cylindrical drum . If the drum rotates too fast, the ingredients remain stuck to the wall of the drum and proper mixing of ingredients does not take place. The maximum rotational speed of the drum in revolutions per minute (rpm) to ensure proper mixing is close to (Take the radius of the drum to be $1.25\, m$ and its axle to be horizontal)

medium

(JEE MAIN-2016)

A particle of mass $m$ is tied to one end of $a$ string of length $l$. The particle is held horizontal with the string $mg$ taut. It is then projected upward with $a$ velocity $u$. The tension in the string is $\frac{{mg}}{2}$ when it is inclined at an angle $30^o$ to the horizontal. The value of $u$ is

hard

A weightless thread can bear tension upto $3.7\, kg wt.$ A stone of mass $500\, gms$ is tied to it and revolved in a circular path of radius $4 m$ in a vertical plane. If $g = 10\,m{s^{ – 2}}$, then the maximum angular velocity of the stone will be …….. $rad/\sec$

medium

A particle is kept at rest at the top of a sphere of diameter $42\, m$. When disturbed slightly, it slides down. At what height $‘h’ $ from the bottom, the particle will leave the sphere …….. $m$

hard

A stone of mass $150\ g$ moves in a vertical circle on the end of a length of string. The radius of the cirlce is $70\ cm$ and the speed of the stone at the topmost point $P$ is $3.5\ m/s$ . For the instant at which the stone passes through the highest point $P$ , the centripetal force is nearly ……… $N$ (take $g = 10\ m/s^2$ )

medium