IB myp 4-5 physics – Practice Questions- All Topics
Topic :Forces and energy-Work and Power,Efficiency transfer and transformation of energy, conservation of energy
Topic :Forces and energy– Weightage : 21 %
All Questions for Topic : Work, energy, power, conservation \& transformation of energy, efficiency
Question
Select appropriate terms and organize them into a sequence to show the energy changes taking place in the circuit.
▶️Answer/Explanation
Ans:
Sequence of energy changes in the circuit:
1. Chemical energy (from a battery or power source)
2. Electrical energy (as current flows through the circuit)
3. Light energy (if a light bulb or LED is present in the circuit)
4. Sound energy (if a sound-producing device, such as a buzzer, is present in the circuit)
5. Electrical energy (as current continues to flow through the circuit)
6. Nuclear energy (if the circuit involves a nuclear power source, such as a nuclear reactor)
Question:
A runner covers 3,000m in 13 minutes. If she has a mass of 55kg, calculate her kinetic energy.
▶️Answer/Explanation
Ans: \(v = \frac{3000}{13\times 60}\) = 3.85 m s–1; Ek = ½(55)(3.85)2 = 408 J
Question:
A man of mass 75kg climbs up the stairs to the top of a 180m high tower block. What is his increase in gravitational potential energy?
▶️Answer/Explanation
Ans: The size of the effective nuclear charge (which depends on the group number) and the level of shielding provided by the electron shells (which depends on the period number).