Physics Problems

Electricity and Motion

• The SI derived unit of voltage is the volt (V).
• The kinematic formula Δ𝜗 = 𝜔𝑖Δ𝑡 + 𝛼 ⁽²⁾(Δ𝑡)² is valid for certain types of motion.
• A magnetic field surrounds a long, straight wire carrying a current, and the field's direction is perpendicular to the wire.
• The electric force between two oppositely charged particles is attractive.

Balancing Forces

• When a 1.00-kg mass is hung from a set of balance scales, an unknown mass m balances the scales when placed 0.30 m from the pivot point.
• The value of m can be calculated using torque and rotational equilibrium.

Motion with Constant Velocity

• An aeroplane in a horizontal turn with a constant speed has a net force acting on it, which is not zero.
• The work done on a particle by a force F ≠ 0 as it moves through a displacement Δr is maximum when Δr is in the direction of F.

Electric Circuits

• The loop law ∑ℰ + ∑V = 0 is a consequence of applying the law of conservation of energy to the flow of current around a closed loop.
• In a series circuit with resistances of 2.0 Ω, 4.0 Ω, and 6.0 Ω and a 24-V battery, the current in the 4.0 Ω resistor can be calculated using Ohm's law and Kirchhoff's laws.