Why does a motor take more current when we start it?

Why do we need to take food?

Why does micelle formation take place when soap is added to water? will a micelle be formed in other solvents such as ethanol also?

Why does current flow in acids?

Why does a metallic piece become very hot, when it is surrounded by a coil carrying high frequency alternating current?

Why does a child feel more pain when she falls down on a hard cement floor, then when she falls on the soft muddy ground in the garden?

When does a source of current deliver maximum power?

Why a horse has to apply more force to start a tonga than to keep it moving?