The wheel in figure has eight equally spaced spokes and a radius of 30 cm. It is mounted on a fixed axle and is spinning at 2.5 rev/s. You want to shoot a 20-cm-long arrow parallel to this axle and through the wheel

Question

The wheel in figure has eight equally spaced spokes and a radius of 30 cm. It is mounted on a fixed axle and is spinning at 2.5 rev/s. You want to shoot a 20-cm-long arrow parallel to this axle and through the wheel <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/0791b3d3211f2c41b9a6f3cbe7771b91-.png" /> (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

To avoid touching the spokes, the arrow must go through the wheel in not more than

Δ t = \frac{1/8 re V}{2.5 re V / s} = 0.050 s

The minimum speed o the arrow is then

v_{min} = \frac{20 c m}{0.050 s} = 400 c m / s = 4.0 m / s

Q. The wheel in figure has eight equally spaced spokes and a radius of 30cm. It is mounted on a fixed axle and is spinning at 2.5rev/s. You want to shoot a 20−cm-long arrow parallel to this axle and through the wheel

To avoid touching the spokes, the arrow must go through the wheel in not more than Δt=2.5reV/s1/8reV​=0.050s The minimum speed o the arrow is then vmin​=0.050s20cm​=400cm/s=4.0m/s

Q. The wheel in figure has eight equally spaced spokes and a radius of $30 c m$ . It is mounted on a fixed axle and is spinning at $2.5 re v / s$ . You want to shoot a $20 - c m$ -long arrow parallel to this axle and through the wheel

To avoid touching the spokes, the arrow must go through the wheel in not more than
$Δ t = \frac{1/8 re V}{2.5 re V / s} = 0.050 s$
The minimum speed o the arrow is then
$v_{min} = \frac{20 c m}{0.050 s} = 400 c m / s = 4.0 m / s$