MCQ
$A$ ball connected with string is released at an angle $45^o$ with the vertical as shown in figure. Then the acceleration of the box at this instant will be:

[Mass of the box is equal to mass of ball]

  • A
    $g/4$
  • $g/3$
  • C
    $g/2$
  • D
    none of these

Answer

Correct option: B.
$g/3$
b
Let acceleration of box at this is $'a'$(towards right). $F B D$ of ball $w.r.t.$ box

Net force in $O P$ ditection is zero

$\therefore T+\frac{m a}{\sqrt{2}}=\frac{m g}{\sqrt{2}}$

$F B D$ of ball $w.r.t.$ ground

$T \cos 45^{\circ}=m a$

or $T=\sqrt{2} m a$

Substituting in Eq. $( i ),$ we get

$a=\frac{g}{3}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

The time period of oscillation of a bar magnet suspended horizontally along the magnetic meridian is $T_0$. If this magnet is replaced by another magnet of the same size and pole strength but with double the mass, the new time period will be
A crystal diode is a
A particle of mass $m$ starts moving from origin along $x$-axis and its velocity varies with position $(x)$ as $v=k \sqrt{x}$. The work done by force acting on it during first " $t$ " seconds is ...........
One grams of $H_2$ at $27\,^oC$ is mixed with $16\, g$ of $O_2$ at $37\,^oC$. The temperature of the mixture is about ....... $^oC$
Thermopile is used for
Two moles of ideal helium gas are in a rubber balloon at $30^o C$. The balloon is fully expandable and can be assumed to required no energy in its expansion. The temperature of the gas in the balloon is slowly changed to $35^o C$. The amount of heat required in raising the temperature is nearly...... $J$
(take $R$ $=$ $8.31$ $J/mol.K$)
A manometer connected to a closed tap reads $4.5 \times {10^5}$ pascal. When the tap is opened the reading of the manometer falls to $4 \times {10^5}$ pascal. Then the velocity of flow of water is ........  $m{s^{ - 1}}$
When current in a coil changes to $2$ $ampere$ from $8$ $ampere$ in $3 \times {10^{ - 3}}\,\sec ond$, the $e.m.f$. induced in the coil is $2\,volt$. The self inductance of the coil in millihenry is
Two dielectric slabs of constant ${K_1}$ and ${K_2}$ have been filled in between the plates of a capacitor as shown below. What will be the capacitance of the capacitor
A uniform rod of length $L$ has a mass per unit length $\lambda$ and area of cross-section $A$. If the Young's modulus of the rod is $Y$. Then elongation in the rod due to its own weight is ...........