Theory

CH21 - ELECTRONICS

(a) By reference to an amplifier, explain what is meant by \textit{negative feedback}....................................................................

2009 Summer

Theory

CH21 - ELECTRONICS

An amplifier incorporating an operational amplifier (op-amp) has three inputs A, B and C, as shown in Fig. 9.1.Negative feedback is provided by the re...

2009 Winter

Theory

CH21 - ELECTRONICS

(a) (i) On Fig. 9.1, mark, with the letter X, the virtual earth. [1](ii) Explain what is meant by a virtual earth........................................

2010 Summer

Theory

CH21 - ELECTRONICS

(a) Negative feedback may be used in amplifier circuits. State(i) what is meant by negative feedback,....................................................

2010 Summer

Theory

CH21 - ELECTRONICS

(a) Negative feedback may be used in amplifier circuits. State(i) what is meant by \textit{negative feedback},...........................................

2010 Summer

Theory

CH21 - ELECTRONICS

An amplifier circuit incorporating an operational amplifier (op-amp) is shown in Fig. 9.1.Fig. 9.1(a) State(i) the name of this type of amplifier circ...

2010 Winter

Theory

CH21 - ELECTRONICS

An amplifier circuit incorporating an operational amplifier (op-amp) is shown in Fig. 9.1.[Image_1: Diagram showing an operational amplifier circuit]F...

2010 Winter

Theory

CH21 - ELECTRONICS

(a) State three properties of an ideal operational amplifier (op-amp).1. ................................................................................

2010 Winter

Theory

CH21 - ELECTRONICS

(a) An operational amplifier (op-amp) may be used as a comparator. State the function of a comparator....................................................

2011 Summer

Theory

CH21 - ELECTRONICS

(a) State two effects of negative feedback on the gain of an amplifier incorporating an operational amplifier (op-amp). 1. .............................

2011 Winter

Theory

CH2 - MEASUREMENT TECHNIQUES

Measurements made for a sample of metal wire are shown in Fig. 1.1. Fig. 1.1 (a) State the appropriate instruments used to make each of these meas...

2011 Summer

Theory

Kinetic Energy

(a) Explain what is meant by work done. [1] (b) A car is travelling along a road that has a uniform downhill gradient, as shown in Fig. 2.1. ...

2011 Summer

Theory

CH5 - FORCES, DENSITY & PRESSURE

(a) Explain what is meant by centre of gravity. (b) Define moment of a force. (c) A student is being weighed. The student, of weight $W$, stands 0.3...

2011 Summer

Theory

CH9 - DEFORMATION OF SOLIDS

(a) Define, for a wire, (i) stress,    [1] (ii) strain.    [1] (b) A wire of length 1.70 m hangs vertically from a fixed point,...

2011 Summer

Theory

CH20 - D.C. CIRCUITS

(a) A variable resistor is used to control the current in a circuit, as shown in Fig. 5.1. The variable resistor is connected in series with a 12V po...

2011 Summer

Theory

CH5 - FORCES, DENSITY & PRESSURE

(a) State two assumptions of the simple kinetic model of a gas.   [2] (b) Use the kinetic model of gases and Newton's laws of motion to exp...

2011 Summer

Theory

CH15 - SUPERPOSITION

(a) Explain the term interference.   [1] (b) A ripple tank is used to demonstrate interference between water waves. Describe (i) the appa...

2011 Summer

Theory

CH1 - PHYSICAL QUANTITIES & UNITS

(a) Distinguish between scalar quantities and vector quantities. [2] (b) In the following list, underline all the scalar quantities. accelerati...

2011 Summer

Theory

CH1 - PHYSICAL QUANTITIES & UNITS

(a) A sphere of radius $R$ is moving through a fluid with constant speed $v$. There is a frictional force $F$ acting on the sphere, which is given by ...

2011 Summer

Theory

Potential Energy

(a) (i) Explain what is meant by work done. [1] (ii) Define power. [1] (b) Fig. 3.1 shows part of a fairground ride with a carriage on rai...

2011 Summer