# Unit Conversions and Mistakes: Understanding the Basics

• gcombina
In summary, the person is struggling with unit conversions and provides an example of a problem involving a football player kicking a ball. They attempt to solve the problem using the formula F = mv/t but are unsure of their answer due to incorrect units. They mention that they may need a break.
gcombina
Hello, I am having lots of problems with units. I don't know why but I am getting sick of it. I don't know what am I doing wrong.

Let me give you an example.

I have this problem:
A football player kicks a 0.41-kg football initially at rest; and the ball flies through the air. If the kicker's foot was in contact with the ball for 0.51 s and the ball's initial speed after the collision is 21 m/s, what was the magnitude of the average force on the football?

My attempt:

F = mv/t
F = (0.41 kg) (21m/s) / 0.051s
F = (8.61 Kg. m. / s) / 0.051 s
F = (8.61 kg.m) / 0.051 s^2
F = 169 kg.m/s^2

why is my unit so wrong? (kg.m/s^2) (my answer should be in NEWTONS)

Those units of yours are the same as Newtons.

Chet

of course

i think I need a break

Thanks!

## What are the common problems with units in scientific calculations?

The most common problems with units in scientific calculations include using the wrong units, converting between units incorrectly, forgetting to include units in the final answer, using inconsistent units throughout the calculation, and not understanding the difference between base units and derived units.

## How can using incorrect units affect the accuracy of scientific results?

Using incorrect units can greatly affect the accuracy of scientific results. It can lead to incorrect calculations, incorrect interpretations of data, and ultimately, incorrect conclusions. It is important to always double check units to ensure the accuracy of scientific results.

## What is the best way to convert between units in scientific calculations?

The best way to convert between units in scientific calculations is to use conversion factors. These are ratios that relate two different units of the same quantity. By multiplying the original value by the conversion factor, the value is converted to the desired unit.

## Why is it important to include units in the final answer of a scientific calculation?

Including units in the final answer of a scientific calculation is important for several reasons. It provides context for the numerical value, it helps to ensure the accuracy of the answer, and it allows for easy comparison with other values in the same units.

## What is the difference between base units and derived units?

Base units are fundamental, independent units that cannot be expressed in terms of other units. They are used to measure basic physical quantities such as length, mass, and time. Derived units, on the other hand, are combinations of base units and are used to measure more complex quantities such as velocity, acceleration, and energy.

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