Ordinary level 2026 South West regional mock physics 2

I have extracted the data from your latest image, which focuses on Physics and Chemistry topics such as Semiconductors, Linear Momentum, Pressure, Equilibrium, and Radioactivity.

SECTION I (One Hour) – ANSWER ALL QUESTIONS

1. (i) What is a semiconductor? (2 marks)

• (ii) Distinguish between a p-type semiconductor and an n-type semiconductor. (2 marks)

• (iii) Name an application of a combination of a p-type and n-type semiconductor. (1 mark)

• (b) Calculate the number of electrons that flow through a conductor if a current of $8\text{ A}$ flows for $4\text{ s}$ (charge on an electron is $e = 1.6 \times 10^{-19}\text{ C}$). (3 marks)

2. A stationary gun of mass $4\text{ kg}$ fires a bullet of mass $0.05\text{ kg}$ with a velocity of $900\text{ m/s}$ and recoils as a result.

• (i) State the law of conservation of linear momentum. (2 marks)

• (ii) Calculate the momentum of the bullet. (2 marks)

• (iii) Calculate the recoil velocity. (2 marks)

3. Figure 1 shows a u-tube filled with mercury of density $13,600\text{ kg/m}^3$ and connected to a gas supply.

• (i) Name the pressures exerted at points A and B. (2 marks)

• (ii) Calculate the excess pressure of the gas in pascals. (3 marks)

• (iii) Calculate the pressure of the gas if atmospheric pressure is $1.0 \times 10^5\text{ Pa}$. (2 marks)

• (iv) Name one instrument that is an application of the u-tube. (1 mark)

4. Figure 2 shows two loads supported in a see-saw such that they are in equilibrium.

• (a) State the conditions necessary for the system to be in equilibrium. (2 marks)

• (b) If the see-saw plank has negligible weight, calculate the distance, $x$. (2 marks)

• (c) (i) Calculate the upward force, $R$, acting at the pivot? (1 mark)

• (ii) Draw a free-body diagram of the forces acting, showing that the system is stable. (2 marks)

5. Isotopes of carbon are $^{12}_6C$ and $^{14}_6C$.

• (a) What are isotopes? (2 marks)

• (b) Calculate the $N/Z$ ratio for $^{14}_6C$ and state if the isotope is stable or unstable. (3 marks)

• (c) Define half-life of a radioactive sample. (2 marks)

6. Figure 3 shows an electric circuit.

• Calculate:

• (a) The combined resistance of the above circuit. (3 marks)

• (b) The current flowing through the ammeter. (3 marks)

Would you like the step-by-step solutions for the momentum and recoil velocity (Question 2) or the circuit resistance calculation (Question 6)?