{"result":{"text":"ϕ equals B with rightwards arrow on top. A with rightwards arrow on top equals B A cos 60 degree equals 1 over 2500\ntherefore e equals negative fraction numerator d ϕ over denominator d t end fraction equals fraction numerator 1 over denominator 2500 cross times 0.2 end fraction equals 2 cross times 10 to the power of negative 3 end exponent V"},"status":"ok"}