Theory

CH11 - ATOMS AND RADIOACTIVITY

A certain element is known to exist as two different isotopes.(a) State one thing that is the same for atoms of both isotopes............................

2010 Summer

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

Emissions from a radioactive source pass through a hole in a lead screen and into a magnetic field, as shown in Fig. 10.1. Radiation detectors are p...

2010 Winter

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

(a) An atom consists of a nucleus made up of protons and neutrons, surrounded by orbiting electrons.(i) Which of these particles has a positive charge...

2011 Summer

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

A scientist needs to use a source of $\gamma$-rays as safely as possible.Which action will not reduce the amount of radiation that reaches the scienti...

2011 Winter

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

A nuclide of substance X has the symbol $^{26}_{12}X$.How many electrons are there in a neutral atom of substance X?A. 12 B. 14 C. 26 D. 38

2011 Winter

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

The graph shows the activity of a radioactive source over a period of time. What is the half-life of the source? A $\frac{1}{2}$ hour B 1 hour C ...

2011 Winter

3

Theory

CH11 - ATOMS AND RADIOACTIVITY

A radioactive nucleus contains 138 neutrons. The nucleus emits an \( \alpha \)-particle. How many neutrons are in the nucleus after it has emitted th...

2009 Summer

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

The graph shows the decay curve for one particular radioactive nuclide. What is the half-life of this nuclide? A. 1.0 day B. 1.5 days C. 2.0 days D. ...

2009 Summer

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

Which diagram could represent the structure of a neutral atom?[Image_1: Diagrams A, B, C, and D with key indicating neutron, proton, electron]

2012 Summer

2

Theory

CH11 - ATOMS AND RADIOACTIVITY

A radioactive element has a half-life of 70s.The number of emissions per second, $N$, of a sample of the element is measured at a certain time.What wa...

2010 Winter

2

Theory

CH1 - MEASUREMENTS AND UNITS

The diagram shows an enlarged drawing of the end of a metre rule. It is being used to measure the length of a small feather. What is the length of the...

2011 Summer

2

Theory

CH2 - FORCES AND MOTION

An object moves initially with constant speed and then with constant acceleration. Which graph shows this motion?

2011 Summer

2

Theory

CH6 - WAVES AND SOUNDS

A tennis player hits a ball hard and 0.40 s later hears the echo from a wall. The speed of sound in air is 330 m/s.How far away is the player from the...

2011 Summer

1

Theory

CH2 - FORCES AND MOTION

Which statement about mass and weight is correct?A. Mass and weight are both forces.B. Neither mass nor weight is a force.C. Only mass is a force.D. O...

2011 Summer

1

Theory

CH3 - FORCES AND PRESSURE

The diagram shows a balance being used to find the weight of a baby. The weight of the basket can be ignored.At equilibrium, the pivot is nearer to th...

2011 Summer

Theory

CH1 - MEASUREMENTS AND UNITS

A cube of side 2.0 cm is placed on a balance. What is the density of the cube? A. 0.90 g/cm³ B. 1.2 g/cm³ C. 1.8 g/cm³ D. 3.6 g/cm³

2011 Summer

1

Theory

CH3 - FORCES AND PRESSURE

Objects with different masses are hung on a spring. The diagram shows how much the spring stretches.The extension of the spring is directly proportion...

2011 Summer

Theory

CH4 - FORCES AND ENERGY

Which row gives an example of the stated form of energy?[Table_1]form of energy | exampleA gravitational | the energy due to the movement of a train a...

2011 Summer

1

Theory

CH4 - FORCES AND ENERGY

Which energy resource is used to generate electricity by first boiling water? A. hydroelectric B. nuclear fission C. tides D. waves

2011 Summer

1

Theory

CH4 - FORCES AND ENERGY

Two farmers use an electrically powered elevator to lift bales of hay. All the bales of hay have the same mass. As sunset approaches, they increase...

2011 Summer