Expert Physics Tutoring

MS1

- Work done is the energy transferred to an object by a force that moves the object in its own direction (1)

- Unit is Joules (J) (1)

MS2

- Identifies correct equation: v² = u² + 2as (1)

- Substitutes values correctly: 10² = 0 + 2*(-9.8)*h (1)

- Rearranges for h: h = 5.1m (rounded to 2sf) (1)

MS3

- The total amount of energy in a closed system remains constant, although it can be transformed from one type to another (2)

MS4

- Identifies correct equation: Power = Work done / Time (1)

- Calculates work done: 1/2*1000*(20)² (1)

- Substitutes values, units (Joules & seconds) (1)

- Final answer: 40kW (1)

MS5

- Energy is lost due to:

- Elastic deformation of the ball (1)

- Air resistance (1)

MS6

- Identifies correct equation: Work Done = Force × distance (1)

- Calculates force: F = mg (1)

- Substitutes values, units (N & meters) (1)

- Final answer: 19600J (1)

MS7

- Elastic potential energy (2)

MS8

- Water stored behind the dam has gravitational potential energy (1)

- When water is released, potential energy is converted to kinetic energy (1)

- Kinetic energy drives turbines, which convert it into electrical energy (1)

MS9

- Energy efficiency refers to minimizing energy loss in a system (1)

- Example: using LED bulbs instead of incandescent bulbs (1)

MS10

- Converts power to energy: 100J/s × 5h (1)

- Multiplies time by seconds in an hour (1)

- Final answer: 1.8MJ (1)