sheet
CLASS 10 PHYSICS
FORMULAS
1. Light - Reflection and Refraction
• Mirror formula: 1/f = 1/v+1/u
• Lens formula:1/f = 1/v-1/u
• Magnification(m): For mirrors : m=-v/u
For Lens : m=v/u
• Power of a lens(P): P=1/f(in meters)
2. Electricity
• ohm's law : V=IR
• Resistance in series : Rs = R1+ R2+R3
• Resistance in parallel : 1/Rp = 1/R1+1/R2+1/R3
• Electric power(P) : P = VI = I2R = V2/R
• Joule's Law of Heating : H = I2Rt