Wave speed is given in meters per second (the number of waves that pass per second). Wavelength is measured in meters and frequency is measured in hertz (Hz), or number of waves per second. Demo In this tutorial you will learn how to calculate the speed of a wave. The equation for this calculation is written like this: $v = { \text f \; \text x \; \lambda }$ Chilled practice question Calculate the velocity of a wave with a wavelength of 6 m and a frequency of 50 Hz Frozen practice question Find the velocity of a wave which has a time period of 10 s and a wavelength of 24 m, you will need to calculate the frequency from the wave period equation first. Science in context Wave speed is given in meters per second (the number of waves that pass per second). Wave Speed = Frequency x Wave length. Wavelength is measured in meters and frequency is measured in hertz (Hz), or number of waves per second.
An object of constant mass accelerates in proportion to the force applied. Demo In this tutorial you will learn how to calculate the force applied to an object if you are given its mass and acceleration. The equation for this calculation is written like this: $F = { \text m\; \text x \; \text a}$ Chilled practice question Calculate the force applied to cannon ball which accelerates at 7m/s2 which has a mass of 5 Kg. Frozen practice question A rocket has a driving force of 15 N and a mass of 250 g. Calculate the acceleration of the rocket. Science in context Force (N) = mass (kg) × acceleration (m/s²). Therefore, an object of constant mass accelerates in proportion to the force applied.
In physics, the kinetic energy (KE) of an object is the energy that it has due to its motion. It is defined as the work needed for an object of a known mass to accelerate to a given velocity. What is Kinetic energy? In physics, the kinetic energy (KE) of an object is the energy that it has due to its motion. It is defined as the work needed for an object of a known mass to accelerate to a given velocity. Kinetic energy equation To calculate Kinetic energy we write the equation like this. $E_k = { 1 \over2} mv {^2}$ Kinetic energy demo In this tutorial you will learn how to calculate the energy stored in a moving object. 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 Kinetic energy store in a car with a mass of 850 Kg moving at a velocity of 3.5 m/s. Frozen practice question Copy out the question and attempt to calculate the answer before watching the solution. Write…
The radioactivity of a sample decreases over time. Half life is a measurement of this decrease. What is Half life? The radioactivity of a sample decreases over time. Half life is a measurement in this decrease.The half-life of a radioactive substance is a constant for each radioactive material. It measures the time it takes for a known amount of the substance to become reduced by half due to radioactive decay, and therefore, the emission of radiation. Half life demo In this tutorial you will learn how to calculate the half life of a radioactive material. Chilled practice question The activity of a radio-isotope is 1536 cpm. What is its activity after five half lives? Frozen practice question A radio-isotopes activity falls from 1880 cpm to 235 cpm in 72 minutes. Calculate it’s half life. Science in context The radioactivity of a sample decreases over time. Half life is a measurement of this decrease
Lifting an object in a gravitational field transfers energy into the objects gravitational energy store. Gravitational potential energy is the energy an object has due to its height above Earth. What is Gravitational potential energy? Lifting an object in a gravitational field transfers energy into the objects gravitational energy store. Gravitational potential energy is the energy an object has due to its height above Earth. The equation for gravitational potential energy is GPE = mgh, where m is the mass in kilograms, g is the gravitational field strength (9.8 N/Kg on Earth), and h is the height above the ground in meters. Gravitational potential energy equation To calculate Gravitational potential energy we use this equation. $E_p = mgh$ Gravitational potential energy demo In this tutorial you will learn how to calculate the energy stored in an elevated object. 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. A barrel is lifted onto a shelf 3.5 m from the ground. The barrel has a mass of 22 Kg.…
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…
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.
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 change in momentum and the affect it has on impact forces. The equation is written like this: $F = { mv \unicode{x2013} mu \over \text{t}}$ Chilled practice question Calculate the force acting if there is a change in momentum from zero to 168 Kgm/s for 7 s. Frozen practice question A 50 kg gymnast is thrown in the air and travels at 5 m/s. The contact time to throw the gymnast is 0.5 seconds. Calculate the force acting on the gymnast. 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.
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.
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.
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.
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.…
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.