Basics of A-Level of Physics

Question 1

Prefixes: What are all the prefixes?

Answer 1

Terra (T), Giga (G), Mega (M), Kilo (k), Centi (c), Milli (m), Micro (u with one long side), Nano (n), Pico (p)

Question 2

Power of Ten for Terra

Answer 2

X10^12

Question 3

Power of ten for Giga

Answer 3

X10^9

Question 4

Power of ten for Mega

Answer 4

X10^6

Question 5

Power of ten for kilo

Answer 5

X10^3

Question 6

Power of ten for Centi

Answer 6

X10^-3

Question 7

Power of ten for Milli

Answer 7

X10^-3

Question 8

Power of ten for Micro

Answer 8

X10^-6

Question 9

Power of ten for Nano

Answer 9

X10^-9

Question 10

Power of ten for Pico

Answer 10

X10^-12

Question 11

When you have really large or small numbers what should you convert them to?

Answer 11

Always to the power of ten I.e. 65x10^-3, 3x10^-2

Question 12

What are the BASE S.I units

Answer 12

Mass (kg), length (m), time (s), current in ampere (A), Temperature (k), Amount of substance (mol), luminous intensity in candela (c.d)

Question 13

What are the derived units?

Answer 13

Voltage (v), Power (W), Energy (J), Velocity (ms-1), acceleration (ms-2), Pressure (Pa), Force (N), Density (Kgm-3), Temperature (°C)

Question 14

What is the base unit of 1N?

Answer 14

1kgms^-2

Question 15

What is the base unit of 1J?

Answer 15

1kgm^2s^-2

Question 16

What is the base unit of 1Pa

Answer 16

1kgm^-1s^-2

Question 17

What are random errors?

Answer 17

These cause unpredictable fluctuations in an instrument’s readings as a result of uncontrollable factors, such as environmental conditions. This affect the precision of the measurements taken, causing a wider spread of results the mean value.

Question 18

How do use reduce the amount of random errors?

Answer 18

Repeat measurements several times and calculate an average from them.

Question 19

Systematic errors

Answer 19

Systematic errors arise from the use of faulty instruments used or from flaws in the experimental method. This type of error is repeated consistently every time the instrument is used or the method is followed, which affects the accuracy of all readings obtained.

Question 20

How do you reduce systematic errors?

Answer 20

Instruments should be recalibrated, or different instruments should be used. Corrections or adjustments should be made to the technique.

Question 21

What are zero errors?

Answer 21

This is a type of systematic error which occurs when an instrument gives a reading when the true reading is zero. This introduces a fixed error into readings which must be accounted for when the results are recorded.

Question 22

What is precision?

Answer 22

Precise measurements are ones in which there is very little spread about the mean value.

Question 23

What is accuracy?

Answer 23

A measurement is considered accurate if it is close to the true value.

Question 24

What is repeatability?

Answer 24

A measurement is repeatable if the original experimenter repeats the investigation using the same method and equipment and obtains the same results.

Question 25

What is reproducibility?

Answer 25

A measurement is reproducible if the investigation is repeated by another person, or by using different equipment or techniques, and the same results are obtained.

Question 26

What is resolution?

Answer 26

The smallest change in the quantity being measured of a measuring instrument that gives a perceptible change in the reading.

Question 27

Percentage uncertainty equation

Answer 27

Percentage uncertainty = Uncertainty/measured value x 100