CSEC Physics Paper 2 January 2015 - Free CXC Past Paper with Answers

One of the things that physics is concerned with is the study of energy. Complete Table 2 to show two other major forms of energy and ONE example of each.

TABLE 2

State the SI unit of energy.

Define the SI unit of energy named in (ii) above.

A bucket filled with cement of total mass 60 kg is raised vertically 150 m from the ground to the twelfth floor of a building under construction as shown in Figure 1.

Calculate the amount of energy that was needed to perform this activity. (Assume no frictional forces were present.)

If this activity takes 25 seconds to complete, calculate the power utilized in kilowatts.

If friction was present, what effect if any, would this have on the power needed?

(Gravitational field strength, $g = 10 \text{ N kg}^{-1}$)

Dr T likes to measure temperatures. From his temperature bag, shown in Figure 2, select the two temperatures to complete Table 3.

TABLE 3

Define the term ‘lower fixed point’.

In Table 4, enter the names of two different types of thermometers and the corresponding physical quantity which varies with temperature.

TABLE 4

A motor car tyre contained a fixed mass of air at $27 \text{ °C}$. Its pressure was $220 \text{ kN m}^{-2}$ above atmospheric pressure. After a 60-minute drive, the air pressure rose to $250 \text{ kN m}^{-2}$ above atmospheric pressure.

SECTION B

Answer ALL questions.

You MUST write your answers in the spaces provided after each question.

4. (a) (i) With the aid of a labelled diagram, state the laws of reflection. Write your answer to Question 4 (a) (i) here.

Diagram for Question 4 (a) (i)

With the aid of a labelled diagram, state the laws of reflection.

The glare of light from oncoming vehicles when driving on a rainy night can be annoying. With the aid of a labelled diagram, show how this glare results. Write your answer to Question 4 (a) (ii) here.

Diagram for Question 4 (a) (ii)

A pencil is placed in a glass of water and appears to be bent as shown in Figure 3 below.

Calculate the refractive index of the water which causes this apparent bending if angle $a = 32 \text{°}$ and angle $b = 45 \text{°}$.

If the pencil is now placed in ethanol with a refractive index of 1.36, calculate the new angle $b$ given that angle $a$ in the ethanol remains at $32 \text{°}$.

Does the pencil bend more or less in ethanol than in water? Justify your answer.

Write your answer to Question 5 (a) here.

State the formula that relates the potential difference across a metallic conductor at constant temperature to the current through it.

State the formula that expresses the total resistance, $R_T$, of two resistors, $R_1$ and $R_2$, in parallel.

The brightness of the incandescent bulb in Figure 4 may be increased by varying the rheostat between $0 \Omega$ and $100 \Omega$. When lit, the bulb operates at $0.30 \text{ A}$ and $3.0 \text{ V}$.

What is the resistance of the bulb?

Assuming the resistance of the bulb remains constant once lit, calculate the ammeter reading if the rheostat is set to $100 \Omega$.

Is there a danger in reducing the rheostat resistance too much? Explain.

The assumption made in (b) (ii) is incorrect. With the aid of an I–V graph, indicate how the bulb’s resistance actually varies with current.

In order to separate the emissions from a radioactive source, they are subjected to a uniform electric field, E, perpendicular to their path as shown in Figure 5.

Describe the path of each of the three emissions ($\alpha$, $\beta$ and $\gamma$) when subjected to a uniform electric field from left if the emissions are projected up towards the top of your page.

If the electric field is replaced by a uniform magnetic field into the page, predict the path of the emissions.

Write your answer to Question 6 (a) here.

One isotope of lead $_{82}^{210}\text{Pb}$ is not stable but can undergo exactly three distinct decays of an alpha or beta particle to become stable lead.

With reference to the information in Table 5, write a possible sequence of three nuclear equations that can result in $_{82}^{206}\text{Pb}$ (stable lead) from .

Calculate the energy given off in a nuclear reaction if the change in mass is $0.2014 \text{ u}$. ($\text{u} = 1.66 \times 10^{-27} \text{ kg}$; $\text{c}=3.0\times {10}^8{\text{ ms}}^{}$).