You’re swimming. You push the water back to move forward. Why does pushing the water back, move you forward? Which one of Newton’s Laws is this an example of?

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

What are similarities and differences between refraction, reflection, diffraction and absorption?

Acapacitor is storing energy of 3 joules with a voltage of 50 volts across its terminals. a second identical capacitor of the same value is storing energy of 1 joule. what is the voltage across the terminals of the second capacitor?