1. The basics The most crucial components that I will be looking at are the batteries, the motor, the gears and the springs that allow the mechanism to function. The designers needed to ensure several things; Enough voltage and enough current to drive the motor. - these amplified with the aid of a resistor connected to the motor. Make sure that motor has high enough torque to overcome the spring constant to pull the spring. Spring needs to have enough force to pull back the scope. All workings are theoretical and therefore will have some minor assumptions that have not been taken into account such as inertia within the motor, inertia of the gears, frictional losses and even down to the manufacturing's of the spring.

2. BATTERIES WHAT? 4 1.5V AA R06 Battery supplies power to motor- to little gear, which at a certain speed will supply a specific torque Power is being supplied by the batteries V=Voltage: 3V (Series/Parallel Circuit) =Work Done Doubles battery capacity And increases voltage

3. MOTOR Resistor: 2.2 ohms and 5 % tolerance Power given to motor = current^2 * Resistance Current: (Amps) I=V/R= 3/2.2= 1.36 A R=resistance V=Voltage Power to motor: (Joules per second) current^2 * Resistance =1.36^2*2= 4.07 Watts

4. example motor To do my calculations I used the information from a small DC motor as the motor in the system did not have any indication of its specifications. Power= 1.6 W 1.5  3V dc 2mm shaft diameter Rotations per minute= 7800 rpm

5. GEARS Size of the gears manipulate the speed at which it will rise. The gear ratio will affect the speed at which the spring gets extended. Torque that the gear needs to overcome the force of the spring (static balance) One gear is driving gear; Driving gear: 10mm diameter= 0.005m radius Second gear= 30mm diameter= 0.015m radius Torque=Force*radius of the gear Force =the spring is applying on the gear T=torque motor provides to the gear to overcome force of the spring The power of the gear P=T*angular speed T=Torque Omega= angular speed- motor speed RPM (converted into radians per second)

6. With example motor… 1cm diameter=0.5 radius small gear GCM= gram cm Maximum torque: 20gcm = 0.00196 Nm 0.00196/0.005=Force at radius of driving gear (N) =0.392 N That force is driving force on second gear. Meaning that is the force at edge of first gear which will exert an equal force on the second gear. *By radius of second gear(0.015)= second torque (Nm) =0.392*0.015 =0.00588 N That is the torque at the centre of that second gear This can be used that to find force that is exerted on the spring. P=T*angular speed 0.00588*7800= 45.864

7. SPRING Spring has to have enough force to overcome the moment of inertia within the motor. Also sufficient force to pull back the scope. Linear spring…. F=kx (hookes law) X= distance spring has to be pulled F= force applied to move spring K= spring constant F is force needs to be applied to move the spring a certain distance This mechanism uses the gears to pull spring.

8. With example motor… With example of motor : F/x in meters= k value of the spring Needs to be held in place statically so want k value that is less than that so that the motor can pull it. K=F/x 45.864/0.01=4586.4 N/m

9. SPeakers AC Current powers the speakers to function; For the speaker to make sound, the driver needs to both move in and out by changing directions of the current flow. It is this movement of the speaker driver moving in and out that is vibrating the air to make sound. So, sound is made by AC, because music is made up of variations of many different frequencies and loudness, with low frequency as the bass, high frequency as treble, and the amplitude of the current expressed as the loudness variation.