# example problem

## Impulse and Momentum – Physics Example Problem

Impulse and momentum are physical concepts that are easily seen from Newton’s Laws of Motion. Start with this equation of motion for constant acceleration. v = v0 + at where v = velocity v0 = initial velocity a = acceleration t = time If you rearrange the equation, you get […]

## Moving Clocks Run Slower – Time Dilation

Special relativity theory introduced an interesting notion about time. Time does not pass at the same rate for moving frames of reference. Moving clocks run slower than clocks in a stationary frame of reference. This effect is known as time dilation. To calculate this time difference, a Lorentz transformation is […]

## Moving Rulers Are Shorter – Length Contraction Example Problem

Relativity tells us moving objects will have different lengths in the direction of motion, depending on the frame of reference of the observer. This is known as length contraction. This type of problem can be reduced to two different frames of reference. One is the frame of reference where a […]

## How Fast Would You Have To Go To Make A Red Light Look Green? – Relativistic Doppler Effect

Everyone knows about the doppler effect with sounds. When a train approaches, the pitch of its sound increases. After it passes, the pitch seems to drop off. This is because the sound waves are compressed (wavelength shortened/frequency increased) ahead of a moving sound source. The sound waves expand (wavelength increased/frequency […]

## How To Find the Limiting Reactant – Limiting Reactant Example

Many chemical reactions take place until one of the reactants run out. This reactant is known as the limiting reactant. Often it is straightforward to determine which reactant will be the limiting reactant, but sometimes it takes a few extra steps. For example, burning propane in a grill. The propane […]