aqa-synergy-paper-3-and-4-solution Archives - Page 2 of 2 - Fridge Physics

aqa-synergy-paper-3-and-4-solution

Efficiency

The efficiency of a device is the proportion of input energy that is converted to useful energy.

What is Efficiency?

The efficiency of a device is the proportion of input energy that is converted to useful energy. Efficiency is a measure of how much work or energy is conserved in an energy transfer, work or energy can be lost, for example as wasted heat energy. The efficiency is the useful energy output, divided by the total energy input, and can be given as a decimal always less than 1 or a percentage. No machine is 100% efficient.

Efficiency equation

To calculate Efficiency we use this equation.

$efficiency = {\text{useful energy output} \over\text{total energy input}}$

Efficiency demo

In this tutorial you will learn how to calculate how efficient a device is at transferring energy from one form to another.

Chilled practice question

Calculate the efficiency of a light bulb with a total input energy of 500 J. The bulb emits 200 J of light energy and 300 J of heat energy.

Frozen practice question

A tumble drier is 80% efficient. Its useful energy is 45 KJ what is the total input energy in Joules.

Science in context

The efficiency of a device is the proportion of the total input energy that is converted to useful energy.

Millie’s Master Methods

The Fridge Physics Store

Energy Transformed

The potential difference between two points is the energy transferred per unit charge. An electrical circuit is an energy transformation device.

What is Energy transformed?

The potential difference between two points is the energy transferred per unit charge. An electrical circuit is an energy transformation device. Energy is provided to the circuit by an electrochemical cell, battery, generator or another electrical energy source. Energy is delivered by the circuit. The rate at which this energy transformation takes place has a great relevance to the design of an electrical circuit for useful functions.

Energy transformed equation

To calculate Energy transformed we use this equation.

Energy = power x time

$ {\mathit E \, \text = \mathit P \mathit t}$

Energy = charge flow x potential difference

$ {\mathit E \, \text = \mathit Q \mathit V}$

Energy transformed demo

In this tutorial you will learn how to calculate the energy transformed through an electrical circuit.

Chilled practice question

Calculate the energy transformed if a circuit is supplied with 6 V and 32 C of charge flows.

Frozen practice question

Calculate the energy transformed when a current of 4 A flows with a p.d of 230 V for 18 s.

Science in context

The potential difference between two points is the energy transferred per unit charge

Millie’s Master Methods

The Fridge Physics Store

Forces and Work Done

The unit for work done is the joule (J), or Newton meter (N-m). One joule is equal to the amount of work that is done when 1 N of force moves an object over a distance of 1 m.

Demo

In this tutorial you will learn how to calculate the work done to move an object through a known distance.

Note-Some mobile devices may require you to tap full screen during playback to view video content.

The formula for this equation is written like this:

w = f x d

Chilled practice question

Copy out the question and attempt to calculate the answer before watching the solution. Write down the equation and show all of your working, remember to add the units to your answer, this routine will guarantee you maximum marks in an exam. Mark your solution and correct if needed.

How much work has been done if a car is pushed along the road 550 cm with a force of 400 N ?

Frozen practice question

Copy out the question and attempt to calculate the answer before watching the solution. Write down the equation and show all of your working, remember to add the units to your answer, this routine will guarantee you maximum marks in an exam. Mark your solution and correct if needed.

75 J of work is done pulling a trolley 150 cm. Calculate the force applied.

Science in context

Work can be calculated with the equation: Work = Force × Distance. The unit for work is the joule (J), or Newton • meter (N • m). One joule is equal to the amount of work that is done when 1 N of force moves an object over a distance of 1 m.

Millie’s Master Methods

The Fridge Physics Store

Momentum

All moving objects have momentum. Forces can cause changes in momentum. The total momentum in a collision or explosion is conserved and stays the same. Car safety features absorb energy involved in a crash they slow down the collision thus reducing the force of impact.

Demo

In this tutorial you will learn how to calculate the momentum in a moving object.

The equation is written like this:

$P = { \text m\; \text x \; \text v}$

Chilled practice question

Calculate the momentum of a 1200 Kg vehicle travelling at 5 m/s.

Frozen practice question

A girl has a mass of 60 Kg. How fast is she moving if her momentum is 240 Kgm/s ?

Science in context

All moving objects have momentum. Forces can cause changes in momentum. The total momentum in a collision or explosion is conserved and stays the same. Car safety features absorb energy involved in a crash they slow down the collision thus reducing the force of impact.

Millie’s Master Methods

The Fridge Physics Store

Uniform Acceleration

Uniform or constant acceleration is a type of motion in which the velocity of an object changes by an equal amount in every equal time period.

Demo

In this tutorial you will learn how to calculate uniform acceleration.

The equation is written like this:

${ \text v^{2} \; \text – \; \text u^{2} \; \text = \; \text 2as}$

Chilled practice question

A racing car travelling at 20 m/s decelerates uniformly at 1.5 m/s2 towards a slip road 100 m away. Calculate its velocity when it reaches the slip road.

Frozen practice question

A ball is dropped 12 m from the top of a building. Calculate the velocity of the ball when it hits the ground. Ignore any value for air resistance. Acceleration due to gravity is 9.8m/s2

Science in context

Uniform or constant acceleration is a type of motion in which the velocity of an object changes by an equal amount in every equal time period.

Millie’s Master Methods

The Fridge Physics Store

Acceleration

Acceleration is how quickly the velocity is changing whether it be speed, direction or both. Acceleration is a measure of how quickly the velocity of an object is changing.

Demo

In this tutorial you will learn how to calculate the acceleration of a moving object.

The equation is written like this:

$a = { v \unicode{x2013} u \over \text{t}}$

Chilled practice question

Calculate the acceleration if the velocity increases from 4 m/s to 76 m/s in 8 s.

Frozen practice question

How long does it take for the velocity of a bus to increase from 12 m/s to 20 m/s if it is accelerating at 4 m/s2.

Science in context

Acceleration is how quickly the velocity is changing whether it be speed, direction or both.

Millie’s Master Methods

The Fridge Physics Store

Speed

Speed is how fast an object is moving in no given direction. Velocity is how fast an object is moving in a given direction. In physics, you can calculate the average speed by taking the total distance travelled and dividing it by the total time required to travel that distance.

Demo

In this tutorial you will learn how to calculate the speed of an object, velocity is speed with direction for example 20 m/s north.

The equation is written like this:

$S = { \text D / T}$

Chilled practice question

Calculate the speed of a car which travels 2000 m in 400 s.

Frozen practice question

How long does it take a car to travel 360 m at 12 m/s ?

Science in context

Speed is how fast an object is moving in no given direction. Velocity is how fast an object is moving in a given direction.

Millie’s Master Methods

The Fridge Physics Store

Weight on the Moon

Weight is the force acting on an object due to gravity. The weight of an object is defined as the force of gravity on the object and can be calculated as the mass times the acceleration due to gravity.

Demo

In this tutorial you will learn how to calculate the weight of an object on the moon due to its force of gravity.

The equation is written like this:

${ \textit W} = {\text m \;} {\text x \;} {\text g}$

Chilled practice question

Copy out the question and attempt to calculate the answer before watching the solution. Write down the equation and show all of your working, remember to add the units to your answer, this routine will guarantee you maximum marks in an exam. Mark your solution and correct if needed.

Calculate the weight of a flag pole on the moon, it has a mass of 5 Kg.

Frozen practice question

Copy out the question and attempt to calculate the answer before watching the solution. Write down the equation and show all of your working, remember to add the units to your answer, this routine will guarantee you maximum marks in an exam. Mark your solution and correct if needed.

What is the mass of an oxygen cylinder on the moon if it has a weight of 4.8 N ?

Science in context

Weight is the force acting on an object due to gravity.

Millie’s Master Methods

The Fridge Physics Store

Weight on Earth

Weight is the force acting on an object due to gravity. The weight of an object can be defined as the force of gravity on the object. Since the weight is a force, its unit is the Newton.

Demo

In this tutorial you will learn how to calculate the weight of an object due to the force of the Earths gravity.

The equation is written like this:

${ \textit W} = {\text m \;} {\text x \;} {\text g}$

Chilled practice question

Calculate the weight of a bench on Earth which has a mass of 25 Kg.

Frozen practice question

Calculate the mass of an elephant if it has a weight of 60 KN on Earth.

Science in context

Weight is the force acting on an object due to gravity.

Millie’s Master Methods

The Fridge Physics Store

Scroll to Top