CSEC Physics Paper 2 January 2014 - Free CXC Past Paper with Answers

Figure 1 shows some physical quantities and their units. Draw an arrow from EACH quantity to its unit.

Figure 1

Complete Table 2 to show the names of three forces and a situation in which EACH force acts.

TABLE 2

Patrick and Patricia showed their class a 'magical' balancing act. They both sat on one side of a uniform 6.0 m plank. Patrick sat 1.0 m from the pivot located 0.5 m from the centre of the plank. Patricia sat 0.5 m from the pivot, on the same side as Patrick.

Figure 2 shows the 'magical' balancing act. X represents the pivot point.

Figure 2

Label, as W, the point on Figure 2 where the weight of the plank acts.

Calculate the weight of the plank, W.

If Patrick sat alone on the plank, calculate where he would have to sit in order to maintain his 'magical' balancing act. The pivot remains as before.

State the physical property that varies with temperature in each of the following thermometers.

A laboratory thermometer

A thermocouple

Complete Table 3 which relates the use of a thermometer to its design.

TABLE 3

State Charles' Law.

State Charles' Law.

In a sealed cylinder, the volume of gas is recorded as $40 \text{ cm}^3$ with a temperature of $30^\circ\text{C}$.

What is the percentage increase in volume of the gas if the cylinder is heated until the gas temperature reaches $70^\circ\text{C}$?

State TWO properties of electromagnetic waves.

Visible light is a type of electromagnetic wave. State TWO other types of electromagnetic waves indicating whether the wavelength of each is higher or lower than that of visible light.

Electromagnetic waves of one wavelength are absorbed by a solar panel and waves of a longer wavelength are emitted. If electromagnetic waves of wavelength $\lambda_1 = 2 \times 10^{-7}$ m are absorbed by a solar panel as shown in Figure 3 and waves of wavelength $\lambda_2 = 6.5 \times 10^{-7}$ m are emitted, calculate (a) the frequency in each case (b) the decrease in frequency, $\Delta f$.

We assume that the useful energy transferred to the solar panel is a constant, k, times the decrease in frequency of the e.m. waves. ($E = k\Delta f$). State the corresponding energy transferred, $E_r$, in terms of k.

With a change of conditions, the wavelength of the wave now absorbed by the panel increased to $6 \times 10^{-7}$ m, but the emitted wavelength remains at $\lambda_2 = 6.5 \times 10^{-7}$ m. What fraction of , the original energy transferred, is now transferred to the solar panel?

[Speed of light, $c = 3.0 \times 10^8$ m s$^{-1}$]

the frequency in each case

the decrease in frequency, $\Delta f$.

We assume that the useful energy transferred to the solar panel is a constant, k, times the decrease in frequency of the e.m. waves. ($E = k\Delta f$). State the corresponding energy transferred, $E_r$, in terms of k.

With a change of conditions, the wavelength of the wave now absorbed by the panel increased to $6 \times 10^{-7} \text{ m}$, but the emitted wavelength remains at $\lambda_2 = 6.5 \times 10^{-7} \text{ m}$. What fraction of , the original energy transferred, is now transferred to the solar panel?

With the aid of a diagram, describe an experiment that may be used to investigate the relationship between current, I, and potential difference, V, for a filament lamp. Sketch your expected result.

The power supply shown for the circuit in Figure 4 provides a current of 1 mA to the rest of the circuit. (Figure 4 shows a circuit diagram with a power supply, a switch, a $2 \text{ k}\Omega$ resistor ($R_1$), a $3 \text{ k}\Omega$ resistor ($R_2$), and a $5 \text{ k}\Omega$ resistor ($R_3$). $R_1$ and $R_2$ are in series, and $R_3$ is in parallel with $R_2$.)

Assuming negligible losses in the connecting wires, calculate the required potential difference of the supply.

Calculate the current in the $5 \text{ k}\Omega$ resistor.

If the $2 \text{ k}\Omega$ resistor burns out, what current now flows in the $5 \text{ k}\Omega$ resistor?

A nucleus of a radioactive isotope radium $_{86}^{226}\text{Ra}$ emits an $\alpha$-particle (alpha-particle) when it decays to a nucleus of the element radon, Rn.

Write the equation representing this decay process.

How many neutrons are in the $_{86}^{226}\text{Ra}$ nucleus?

Explain why an atom is normally neutral and stable.

What are 'isotopes'?

Figure 5 shows the structure of the atom of an element X: n: neutrons p: protons e: electrons (Figure 5 shows a Bohr model of an atom with a nucleus containing 5 protons and 6 neutrons, and 5 electrons orbiting the nucleus.)

State the mass number, atomic number and the charge on the nucleus of this atom.

Write the symbol for another possible isotope of X.