If you need the 2009-2011 Papers here they are…

# Category: A Level Physics Chapters

**Permanent link to this article: **https://www.animatedscience.co.uk/2011/unit-1-as-exam-past-papers

May 09 2011

## Why do thick wires have lower resistance?

For a copper wire (at a given temperature) the speed of the electrons depends only on the voltage across it. Imagine a three-lane road and a single-lane road with cars all going at the same speed. More cars pass per second in the wider road even though the speed is the same. More cars (charges) per second means higher current for a given voltage and so smaller resistance.

Here’s an animation showing how thicker wires have a lower resistance.

Since current is the same around a simple series circuit the charges have to go faster where the wire is thinner. Faster charges mean more interactions with the ionic lattice per second and so higher resistance.

**Permanent link to this article: **https://www.animatedscience.co.uk/2011/why-do-thick-wires-have-lower-resistance

Apr 12 2011

## Exam Past Papers Unit 5 & 5D

Here is a zipped file structure to download to your PC. It contains all the exam questions from AQA for Unit 5 from 2002 to 2010. Remember this includes the legacy or old spec papers from 2002-8 which are very similar.

**Permanent link to this article: **https://www.animatedscience.co.uk/2011/exam-past-papers-unit-5-5d

## 6 Forces in Equilibrium

This is a unit where you can really go to town on the problems with the vectors. You must read the specification carefully and make sure that you don’t panic if you can’t do all the problems in the post. I have included lots of vector problems which go 360° where the exam board will tend to stick to 90° only to make it easier. However, I am in the business of teaching vectors in 2D and would say I would be a bad teacher to stop just because the exam board don’t do it. You will need the skills found here if you carry on to a Physics type job later on so why not learn now. Most students say it is really hard at first but then the exam is easy and they get it after a bit of graft!

Also you may find it hard to understand the idea that…

- A diagonal vector can be split into two parts the horizontal and vertical parts which can be treated separately.
- Two forces can be added together to make a resultant.
- An object not moving has a sum of all vertical forces as zero and also all horizontal forces as zero.

If you find this is hard keep going as it will click!

#### Resources

**6.1 Vectors and Scalars**

6.1 Trig Problems (You must have these trig skills before you start the problems)

Unit_7_Statics_Dynamics_Vectors_1 (Easy problems sheet)

6_1_Wires Example (This is an example of resolving – hanging a picture)

Unit_7_Statics_Dynamics_Vectors_2 (Rock Hard Problems Sheet beyond AS/A2)

**6.2 Balanced Forces**

6_2_Resultant Forces Problems (quick fun problems – no answers)

72_Practical_Coplanar_Forces (practical proving coplanar forces)

**6.3 The principle of moments**

6_3_Density_of_Ruler_Prac (Use moments to find out density of ruler)

**6.4 More on moments**

6_4_Bridge_Crane_Prac (Practical showing support forces)

6_4_Putting_Your_Foot_Down_Extension (Nice but more complex sheet on moments in your feet)

**Permanent link to this article: **https://www.animatedscience.co.uk/6-forces-in-equilibrium

## 7 On The Move (Motion)

The trick to this unit is simply to do lots of calculations over and over again. Test out what you think, try out the animations and you will be able to do the exam questions. The nuts and bolts are important for every calculation. Try to set up each problem with a diagram and then apply one of the UAM equations. If the problem is setup correctly you cannot go wrong. Don’t try and wing it!

I have now worked out every problem in the test book for this unit and answers are shown below so if you need help then here is a place to start.

**Resources**

**7.1 Speed and Velocity**

7_1_Problems_svt (Problems sheet)

7_1_Problems_Thrust_SSC_vt (Problems sheet)

**7.2 Acceleration**

7_2_Practical_Acceleration (worksheet + instructions)

incline plane prac example (PDF Example Practical)

Results Trolley Down Ramp (XLS)

**7.3 Motion along a straight line at constant acceleration**

7_3_Problems (Problems sheet)

73_HSW_Equations_of_motion (Problems sheet HSW)

**7.4 Free fall**

7_4_Gravity Worksheet (Problem Sheet)

**7.5 Motion graphs**

7_5_ball_handout (Reading)

7_5_Exam_questions (Problem Sheet)

7_5_vta_graphs (Data logging analysis for angles of drop)

7_5_Practice Questions (More Quick Questions)

**7.6 More calculations on mot ion along a straight line**

7_6_Motion and Forces Exam (Exam Exercise with Example Answers)

**7.7/7.8 Projectile Motion 1**

77_Extension_Projectiles (HSW Activity)

7_8_Practical Sheet (Projectiles Problem sheet in 2D)

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## 8 Motion and force

This is a unit which really many find quite difficult. To help yourself out you must learn Newton’s 1^{st}, 2^{nd} and 3^{rd} law of forces. Without this knowledge you cannot succeed in explaining or reasoning out most questions. Also there is a basic principle of coplanar forces producing a resultant and therefore acceleration. It is simple as it is…

**Big – Small = Resultant in the Direction of Big!**

There is an easy way to remember the laws….

1) **Inertia** – “Objects” – don’t want to move but when moving find it difficult to stop

2) **F=ma **– or ratio F/m = a which is more appropriate. The acceleration on a fat person is found as the ratio of the force of the push to the mass of the person

3) **Opposites** – for every force their is an opposite. Fat person on chair pushing down, chair pushes up to support weight with equal and opposite force.

#### Resources

**8.1 Force and acceleration**

8_1_Newtons Laws (Help sheet)

**8.2 Using F=ma (or F/m = a)**

8**.3 Terminal speed**

83_Terminal Speed Practical (Worksheet – Advanced Extension)

8_3_Termnial V Results for BB (Excel Results)

https://www.hypertextbook.com/facts/JianHuang.shtml

**8.4 On the Road**

https://www.passmytheory.co.uk/learningcentre/stoppingdistance.aspx

**8.5 Vehicle safety**

85_Extension_Vehicle_safety (HSW Worksheet)

85_Practical_Sports Shoe (HSW Worksheet)

**Permanent link to this article: **https://www.animatedscience.co.uk/9-motion-and-force

## 10 Work, Energy and Power

This work builds upon the Y11 work from Additional Science. You should be able to derive the Kinetic Energy formulae, understand the concept of work done and how that can be expressed as an idea of Power. Also the efficiency of devices and some idea about how to apply that to real situations such as solar cells or power stations. The crux of this unit is to be able to construct calculations in your head without the use of usual formulae from a sheet. The way around this is to write down all the quantities that you know and then physically try and express the problem step by step. Don’t try and jump to the answer as you will get it wrong. Also check out your units carefully and check that match.

10 Work and Power Student Booklet

**10.1 Work and energy**

work (Practical Raising Mass)

**10.2 Kinetic energy and potential energy**

10_2_ke_derivation (Help sheet)

102_Table Tennis Practical (Practical Exp)

10_2_kinetic_animation (Quick Comparison Animation)

Bouncing Ball Practical (Excel Blank sheet)

**10.3 Power**

https://www.en.wikipedia.org/wiki/Power_(physics)

**10.4 Energy and efficiency**

104_HSW_the_escalator (HWS Worksheet on Escalators)

10_4_elastic (Practical on Elastic Stored Energy)

10_4_lifting a load (Lifting a Load Efficiency)

10. 4 Conservation of Energy Analysis

**10.5 Renewable energy**

10_5_SOL_A5 (efficiency of solar cells practical)

10_5_SOL_R1 (data sheet for practical)

Results (XLS Example Results)

10_5_solar_size_cost (Real Solar Cell Data Calculator)

10_5_Incident_solar_radiation (Real Solar Cell Data Calculator)

**Permanent link to this article: **https://www.animatedscience.co.uk/10-work-energy-and-power

## 11 Materials

This unit depends on an ability to explain and understand force extensiona and YM graphs. It is one of the easy topics but also easy to drop marks if you don’t learn the graphs. Also take care of your areas and units as mm don’t convert well to m when you square them for an area calculation!

#### Resources

11 Materials Student Booklet (Activities)

No Answers End Unit quiz (End Topic Quiz)

**10.1 Density**

https://www.en.wikipedia.org/wiki/Density

**10.2 Springs**

finding k (Excel Results)

**10.3 Deformation of solids**

11_3_Glass_UTS (Excel Results)

11_3_YM_Wire_Prac (Practical Sheet)

13_3_YM_wire (Excel Results)

11_3_Glass_Properties (Extension Materials)

11_3_YM_metal_rubber (Results and Comparison)

11_3_YM_Silk_Strand (Further Reading)

**10.4 More about stress and strain**

114_Scaling (HSW – Scaling Activity)

11_4_Crystaline_structure_of_solids (Further Reading)

**Permanent link to this article: **https://www.animatedscience.co.uk/11-materials