Current and Circuits · Paper 1 — Free Physics SL Practice Questions

A student connects a $9.0\,\text{V}$ battery to a small motor. The current in the circuit is $0.30\,\text{A}$. How much charge passes through the motor in $2.0$ minutes?

A negatively charged rod is brought close to the metal cap of an uncharged gold-leaf electroscope, without touching it. The gold leaf diverges. The rod is then removed. What is the charge on the gold leaf immediately after the rod is removed?

Two identical conducting spheres, P and Q, are mounted on insulating stands. Sphere P carries a charge of $+6.0 \times 10^{-9}$ C and sphere Q carries a charge of $-2.0 \times 10^{-9}$ C. The spheres are briefly brought into contact and then separated. What is the charge on sphere P after separation?

A negatively charged rod is brought close to, but not touching, the metal cap of an uncharged gold-leaf electroscope. The gold leaves diverge. Which row correctly describes the charge distribution the electroscope while the rod remains in place?