Physics 9702 · AS & A Level · Gravitational potential energy and kinetic energy

Gravitational potential energy and kinetic energy — practice question

(a(i))[1]

Define the term power.

(a(ii))[1]

State the meaning of gravitational potential energy.

(b(i))[2]

An aircraft with mass $1200\,\text{kg}$ climbs at a constant speed of $45\,\text{m s}^{-1}$, as illustrated in Fig. 3.1. Its engine supplies a thrust force of $2.0 \times 10^3\,\text{N}$ to propel the aircraft through the air. The aircraft’s height increases at $3.3\,\text{m s}^{-1}$. Calculate the power produced by the thrust force.

(b(ii).1)[2]

Determine the work done by the thrust force over a time interval of $3.0\,\text{minutes}$.

(b(ii).2)[2]

Determine the increase in gravitational potential energy of the aircraft over a time interval of $3.0\,\text{minutes}$.

(b(ii).3)[1]

Determine the work done against air resistance over a time interval of $3.0\,\text{minutes}$.

(b(iii))[1]

Use your answer in (b)(ii) part 3 to calculate the force due to air resistance acting on the aircraft.

(b(iv))[2]

With reference to the aircraft’s motion, state and explain if the aircraft is in equilibrium.

Worked solution & mark scheme

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