Science - Physics part 1

All measurements are subject to _____________. All instruments used are influenced by external circumstances, and the accuracy of a measurement may be affected by the person making the reading.

A measurement is ________ if it is close to the accepted value.

Answer explanation

e accuracy of an individual measurement depends on the quality and performance of the instrument used to make the measurement.

The _________ of a measurement is the degree of exactness to which it can be reproduced. After taking a lot of measurements, you will find that they are close to each other.

Answer explanation

The precision of an instrument is limited by the smallest division on the measurement scale.

When you read any measuring device, you always record the measurement by... reading the smallest division on the scale and then "guessing at" estimating, the tenth of the smallest division. These estimates create uncertainty!

• True

• False

significant digits also known as

The Balue that an answer is expressed in is determined by ___________ ______

Answer explanation

significant digits are the specific number of digits used to communicate the degree of uncertainty in a measurement

Significant digits are all those digits obtained from a properly taken measurement: all of the certain digits plus the one estimated digit.

• yes

• No

• Maybe

• So

Answer explanation

Which means the picture

The number of significant digits indicates the precision of the measurement. More sig digs mean a less precise measurement

• ture

• False

Indicate the number of the significant digits:

321.0, 321, 0.321, 0.00321, 3.21 and 3.21 x 10⁵

Answer explanation

Leading zeros are not significant

- For example, 0.321 and 0.0321 both consist of only 3 significant digts

Trailing zeros are significant

- For example, 4.00, 400, 4.00x 10⁵ all consist of 3 significant digits

eros in between digits 1-9 are significant

- For example, 204.6 has 4 significant digits, 10.204 has 5 significant digits

Exact numbers have an infinite number of significant digits because they do not involve estimated measurements.

Exact numbers are:

• Whole numbers

• Numbers that are definitons

  e.g. 1000m = 1 km

  1 dozen = 12

• numbers that result from counting objects

  e.g. 40 students

  150 books

• Real numbers