Question

In Fig. shown find the velocity of block m if both the rope ends are pulled with a velocity v.

• A. 2v cosθ
• B. v/cosθ
• C. v/2cos θ
• D. 2v/cosθ

Answer 1

Answer: (B)

v/cosθ

Answer 2

l² = x² + y² or 2l $\frac { \mathrm { dl } } { \mathrm { dt } }$ = 0 + 2y $\frac { d y } { d t }$ ( x is constant its derivative is zero)