Cambridge IGCSE Physics - 0625 - Core Paper 1 2017 Summer Zone 1

A stopwatch is used to time a runner in a race. The diagrams show the stopwatch at the start and at the end of the race. How long did the runner take to run the race?

On Earth, a ball is dropped and falls 2.0 m in a vacuum. The acceleration of the ball at 1.0 m is $10 \text{ m/s}^2$. What is the acceleration of the ball at 0.5 m?

The speed-time graph represents a motorcycle journey.
In which part of the graph is the acceleration equal to zero?
[Image_1: Speed-time graph with sections marked A, B, C, D]

Diagram 1 shows a sealed plastic bottle containing a hollow glass sphere and a steel ball.
Diagram 2 shows the same bottle after it has been shaken.
Diagram 3 shows the same bottle after it has been shaken again until the broken glass is in tiny pieces.



The mass of the bottle and contents in diagram 1 is $m_1$.
The mass of the bottle and contents in diagram 2 is $m_2$.
The mass of the bottle and contents in diagram 3 is $m_3$.

Which statement gives the correct relation between $m_1$, $m_2$ and $m_3$?

A student is weighed on laboratory scales.
Which row about weight and mass is correct?
[Table_1]

A measuring cylinder containing only water is placed on an electronic balance. A small, irregularly shaped stone is now completely immersed in the water. The diagrams show the equipment before and after the stone is immersed.

What is the density of the material of the stone?

A boat is travelling at a steady speed in a straight line across the surface of a lake.
Which statement about the boat is correct?

The diagram shows three uniform, solid wooden blocks with a square cross-sectional area resting on a horizontal table.

Which list puts the blocks in order from the least stable to the most stable?

Energy resources are used to generate electricity.
Which resource is renewable and does not release carbon dioxide when being used to produce electricity?

A student does some simple exercises. In which exercise is the most work done?

The diagram shows a box of dimensions 6.0 cm \times 8.0 cm \times 4.0 cm.


The box rests on a flat horizontal surface.
On which face must the box rest to exert the least pressure?

Two identical fish tanks are filled to the same level with water. One tank contains fresh water. The other tank contains sea-water. Sea-water is more dense than fresh water. Which fish experiences the greatest pressure?

A student has a syringe which has its open end sealed. The syringe is completely filled with a certain substance, as shown in diagram 1. The student pushes the piston of the syringe in as far as possible, as shown in diagram 2.

What is in the syringe?

When a microscope is used to look at smoke particles in air, Brownian motion is observed.
What causes the smoke particles to move at random?

The diagram shows a metal foot bridge located in the Sahara desert where the temperature is much less at night than during the day. The ends of the bridge are firmly fixed to the sides of a narrow valley.
The solid line shows the bridge during the coldest part of the night.
Which dotted line shows the bridge at the hottest part of the day?

Equal masses of two different liquids are put into identical beakers.
Liquid 1 is heated for 100s and liquid 2 is heated for 200s by heaters of the same power.
Each liquid has the same rise in temperature.


Which statement is correct?

It is a warm and humid day. A glass contains an iced drink. Water starts to form on the outside of the glass.

What is the name of the effect by which the water forms?

A copper bar and a wooden bar are joined. A piece of paper is wrapped tightly around the join. The bar is heated strongly at the centre for a short time, and the paper goes brown on one side only. Which side goes brown, and what does this show about wood and copper?

Four identical metal plates are painted either black or white and have either a dull or a shiny surface. They are heated to the same temperature. Which plate radiates thermal energy at the greatest rate?

What causes the change in direction when light travels from air into glass?

The diagram shows rays of light passing through a converging lens. Which labelled arrow represents the focal length of the lens?

Which diagram shows what happens when a ray of white light passes through a prism?

The diagrams show four sources of waves.
Which source produces longitudinal waves?

The table shows different types of wave in the electromagnetic spectrum.

[Table_1]

Where do all the waves travel at the same speed?

A fire alarm is not loud enough and the pitch is too low. An engineer adjusts the alarm so that it produces a louder note of a higher pitch.
What effect does this have on the amplitude and on the frequency of the sound?
[Table_1]

In a child's toy, a metal rod is used to lift metal fish out of a toy pond. The fish are magnetically attracted to the end of the rod. There is no magnetic force between the fish.

[Image_1 showing a diagram of a metal rod and fish in a toy pond]

What are possible materials from which the fish and the rod are made?

Which diagram shows the pattern of magnetic field lines around a bar magnet?

A student rubs a plastic rod with a cloth.
The rod becomes positively charged.
What has happened to the rod?

The circuit shows a $2.0\,\Omega$ resistor and a $1.0\,\Omega$ resistor connected to a 12 V battery.

What is the current in the $2.0\,\Omega$ resistor?

A computer engineer wants the speed of a fan to increase automatically when the temperature inside a computer rises. The engineer knows that a larger current causes the fan to turn more quickly.

Which component should be placed at X to make this happen?

The diagram shows a power supply with a constant electromotive force (e.m.f.). It is connected to a voltmeter, a variable resistor and two identical lamps, P and Q. Both lamps are lit.
The resistance of the variable resistor is increased. The voltmeter reading remains unchanged.
What happens to the brightness of the lamps?

A student connects a variable potential divider (potentiometer) circuit.
As the sliding terminal T is moved from R to S, what happens to the reading on the voltmeter?

A light-dependent resistor (LDR) and a resistor R are connected in a series circuit. Light falls on the LDR.
[Image_1: Circuit Diagram]
The brightness of the light falling on the LDR decreases.
What happens to the resistance of the LDR and what happens to the reading on the ammeter?

[Table_1]
| resistance of LDR | reading on ammeter |
| --- | --- |
| A | decreases | decreases |
| B | decreases | increases |
| C | increases | decreases |
| D | increases | increases |

A circuit-breaker is designed to protect a circuit which usually carries a current of 2A.
The time taken to break the circuit depends on the current, as shown in the graph.
What happens when the current in the circuit is 2A and what happens when the current is 18A?

The diagram shows a transformer with primary coil P and secondary coil S. The input potential difference across coil P is $V_P$. The output potential difference across coil S is $V_S$. The number of turns in coil P is $N_P$. The number of turns in coil S is $N_S$.

Which equation relates the input and output voltages to the numbers of turns in P and in S?

What is the purpose of a relay?

Which row gives the relative charge of an electron, a neutron and a proton?
[Table_1]

An element has two isotopes.
Which row compares the numbers of particles in the nuclei of the atoms of these isotopes?
[Table_1]

A hospital doctor is using a source of $\gamma$-rays for a medical treatment. Each diagram shows a view from above of the treatment room. Which diagram shows the best way to protect the doctor and staff in the corridor from the $\gamma$-rays?

A sample of radioactive isotope is decaying.
The nuclei of which atoms will decay first?