Question bank/JEE Main/Physics

Slider block A moves to the right with constant velocity 6 m/s
in the arrangement as shown in the figure. C and D are points on the
string. If, and are the velocities of B, C and D respectively then,
choose

A$|\overset{\rightarrow}{V_{C}} - \overset{\rightarrow}{V_{D}}| = 4|\overset{\rightarrow}{V_{B}}|$B$|\overset{\rightarrow}{V_{B}} - \overset{\rightarrow}{V_{C}}| = |\overset{\rightarrow}{V_{B}} - \overset{\rightarrow}{V_{D}}| = 2|\overset{\rightarrow}{V_{B}}|$C$|\overset{\rightarrow}{V_{C}}| - |\overset{\rightarrow}{V_{D}}| = 2|\overset{\rightarrow}{V_{B}}|$DAll of the above

Show answer and solution▾

Clearly $v_{C} = 6m/s \downarrow$
By string constraint,
$–6 + V_{B} + V_{B} + V_{B} = 0 \Rightarrow V_{B} = 2m/s \downarrow$
Also, $\frac{V_{C} + V_{D}}{2} = V_{B}$
$\Rightarrow V_{D} = - 2m/s$
$\therefore V_{D} = 2m/s \uparrow$
$|\overset{\rightarrow}{V_{C}} - \overset{\rightarrow}{V_{D}}| = 6 + 2 = 8m/s$
$|\overset{\rightarrow}{V_{B}} - \overset{\rightarrow}{V_{C}}| = 4m/s$
$|\overset{\rightarrow}{V_{B}} - \overset{\rightarrow}{V_{D}}| = 4m/s$
$|\overset{\rightarrow}{V_{c}}| - |\overset{\rightarrow}{V_{D}}| = 6 - 2 = 4m/s$

Source: Grass-G / P-16 Physics paper 25 Nov First.docx