# Solving Velocity Addition Formula: 0.75c+0.75c = 0.96c

• tot
In summary, the conversation discusses the use of special velocity addition formulas and how they can be used to calculate the speed of two objects approaching each other from different directions. It is mentioned that the velocity of the objects can be calculated using the formula c(1.5)/(1+0.3249) = 0.96c, with c representing the speed of light. The conversation also notes that this topic has been discussed before and that 0.96c would be the speed measured by observers on each vehicle.
tot

You have to use these special velocity addition formulas.
like this:
http://img704.imageshack.us/img704/267/screenshot20091206at124.png
then you find out the 0.75c+0.75c = 0.96c
(0.75c+0.75c)/(1+(0.75c*0.75c)/c^2)=

c(1.5)/(1+0.3249)=0.96 c

Last edited by a moderator:

So if one object is approaching me at the speed of 0.75c, and another object is approaching me at the same 0.75c but in direction opposite of the first one, the velocity with which they're closing up on each other is 0.96c?

I know this has been asked a million times, but I've never paid much attention.

.96c is what observers aboard each vehicle would measure as the speed of the other vehicle

## What is the velocity addition formula?

The velocity addition formula is a mathematical equation that describes how to combine velocities in a relativistic context. It takes into account the effects of special relativity, such as time dilation and length contraction.

## How do you solve the velocity addition formula?

To solve the velocity addition formula, you need to plug in the velocities of the two objects in question and then use the formula v = (u + w)/(1 + uw/c^2), where v is the final velocity, u is the velocity of one object, and w is the velocity of the other object.

## What is the significance of 0.75c+0.75c = 0.96c?

This equation shows that when two objects are moving at 0.75 times the speed of light in opposite directions, their combined velocity is not simply 1.5c. Instead, it is slightly less than that, at 0.96c. This demonstrates the effects of special relativity, where velocities do not add up in a simple linear manner as in classical mechanics.

## Why is the result in the velocity addition formula always less than the speed of light?

The result in the velocity addition formula is always less than the speed of light because of the limitations imposed by special relativity. According to this theory, the speed of light is the maximum speed at which any object can travel. So, even when two objects are moving at high speeds, their combined velocity will never exceed the speed of light.

## Can the velocity addition formula be used for any type of motion?

The velocity addition formula is specifically designed for relativistic motion, where speeds are close to the speed of light. It cannot be used for classical motion, where speeds are much lower. Additionally, the formula only applies to objects moving in a straight line and does not take into account other factors such as acceleration or gravitational effects.

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