Physical Quantities And Units

Question 1

Explain the difference between accuracy and precision.

Answer 1

Accuracy: refers to how close measured readings (mean)are to the true value.
Precision: the range of values/ measurements.

Question 2

X = y³/h². State and explain which of these two quantities(both have the same uncertainty) contributes more to the uncertainty in the value of X.

Answer 2

[Which contributes more
+ Why it is so]
y is raised to the power of three which is more significant than h which is raised to a power of 2. (In terms of uncertainty)
Therefore, y contributes more.

Question 3

Convert ms‐¹ to kmh‐1
E.g. 30 ms‐1

Answer 3

108 kmh‐¹

Question 4

State what is meant by the mass of a body.

Answer 4

1. Quantity of matter in a body.
2. Property of a body resisting changes to its motion.