Theory

CH24 - ALTERNATING CURRENTS

A sinusoidal alternating voltage is to be rectified. (a) Suggest one advantage of full-wave rectification as compared with half-wave rectification.&n...

2009 Winter

Theory

CH24 - ALTERNATING CURRENTS

A student is asked to design a circuit by which a direct voltage of peak value 9.0V is obtained from a 240V alternating supply. The student uses a tra...

2010 Summer

Theory

CH24 - ALTERNATING CURRENTS

(a) Explain what is meant by the $\textit{root-mean-square}$ (r.m.s.) value of an alternating voltage.  [2] (b) An alternating voltage $V$ is re...

2010 Summer

Theory

CH24 - ALTERNATING CURRENTS

The variation with time $t$ of the current $I$ in a resistor is shown in Fig. 6.1. The variation of the current with time is sinusoidal. (a) Expla...

2010 Winter

Theory

CH24 - ALTERNATING CURRENTS

An alternating current supply is connected in series with a resistor R, as shown in Fig. 6.1. The variation with time $t$ (measured in seconds) of ...

2011 Summer

Theory

CH24 - ALTERNATING CURRENTS

An alternating current supply is connected in series with a resistor R, as shown in Fig. 6.1. The variation with time $t$ (measured in seconds) of ...

2011 Summer

Theory

CH24 - ALTERNATING CURRENTS

The variation with time $t$ of the output $V$ of an alternating voltage supply of frequency 50 Hz is shown in Fig. 6.1.(a) Use Fig. 6.1 to state (i) t...

2011 Winter

Theory

CH24 - ALTERNATING CURRENTS

The variation with time $t$ of the output $V$ of an alternating voltage supply of frequency 50 Hz is shown in Fig. 6.1. (a) Use Fig. 6.1 to state ...

2011 Winter

Theory

CH24 - ALTERNATING CURRENTS

The components for a bridge rectifier are shown in Fig. 5.1. (a) Complete the circuit of Fig. 5.1 by showing the connections of the supply and of t...

2011 Winter

Theory

CH24 - ALTERNATING CURRENTS

A sinusoidal alternating voltage supply is connected to a bridge rectifier consisting of four ideal diodes. The output of the rectifier is connected t...

2012 Summer

MCQ

CH1 - PHYSICAL QUANTITIES & UNITS

Which unit can be expressed in base units as kg m^2 s^{-2}?

2019 Summer

MCQ

CH1 - PHYSICAL QUANTITIES & UNITS

The luminosity $L$ of a star is given by $L = 4\pi r^2 \sigma T^4$ where $r$ is the radius of the star, $T$ is the temperature of the star and $\si...

2019 Summer

MCQ

CH2 - MEASUREMENT TECHNIQUES

A particle has velocity $V$ at an angle $\theta$ to the horizontal. The components of the particle’s velocity are $V_v$ upwards in the vertical dire...

2019 Summer

MCQ

CH14 - WAVES

A whale produces sound waves of frequency 5 Hz. The waves are detected by a microphone and displayed on an oscilloscope. What is the time-base sett...

2019 Summer

MCQ

CH2 - MEASUREMENT TECHNIQUES

The speed shown on a car's speedometer is proportional to the rate of rotation of the tyres. The variation of the diameter of a tyre as it wears intro...

2019 Summer

MCQ

CH3 - KINEMATICS

A car travels along a straight horizontal road. The graph shows the variation of the velocity $v$ of the car with time $t$ for 6.0 s of its journey. ...

2019 Summer

MCQ

CH3 - KINEMATICS

A stone is thrown horizontally from the top of a cliff and falls into the sea some time later. Air resistance is negligible. Which graph shows how th...

2019 Summer

MCQ

CH17 - ELECTRIC FIELDS

A positive charge of $2.6 \times 10^{-8} \text{ C}$ is in a uniform electric field of field strength $300000 \text{ Vm}^{-1}$. How much work must be ...

2019 Summer

MCQ

CH4 - DYNAMICS

Each diagram illustrates a pair of forces of equal magnitude. Which diagram gives an example of a pair of forces that is described by Newton's third ...

2019 Summer

MCQ

CH3 - KINEMATICS

A stone is dropped from a tall building. Air resistance is significant. The variation of distance fallen with time is shown by the dashed line. A sec...

2019 Summer