A ceiling fan having 3 blades of length 80 cm each is rotating with an angular velocity of 1200 rpm. The magnetic field of earth in that region is 0.5 G and angle of dip is 30°. The emf induced across the blades is N π × 10⁻⁵ V. The value of N is

Question

Accepted Answer

32. ω=(2π×1200)/(60)=40π rad s⁻¹, and only the vertical component acts: B_V=0.5×10⁻⁴ sin 30°=2.5×10⁻⁵ T. ε=1/2B_Vωℓ²=1/2×2.5×10⁻⁵×40π×0.64. ε=32π×10⁻⁵ V, so N=32. The blades are in parallel, so three blades give no more than one.

A ceiling fan having 3 blades of length 80 cm each is rotating with an angular velocity of 1200 rpm. The magnetic field of earth in that region is 0.5 G and angle of dip is 30°. The emf induced across the blades is N π × 10⁻⁵ V. The value of N is _____

Step-by-step solution