EASY
AS and A Level
IMPORTANT
Earn 100

A student obtains the following values of two variables r and Y.

r / cm t / s
6.2 4.6
12.0 6.0

The first value of r has an uncertainty of ±0.2 cm, which is much greater than the percentage uncertainty in t. Do the results show that t2 is proportional to r ?

Important Questions on Practical Skills at AS Level

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(a) A+B

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(b) B-A

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(c) C×D

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(d) BD

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(e) A2

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(f) 2×A

EASY
AS and A Level
IMPORTANT

You measure the following quantities:

A=(1.0±0.4)m  B=(2.0±0.2)m

C=(2.0±0.5)ms-1  D=(0.20±0.01)s

Calculate the result and its uncertainty for each of the following expressions. You may express your uncertainty either as an absolute value or as a percentage.

(g) The square root of (A×B). (Recall that the square root of x can be written as x1/3.)

EASY
AS and A Level
IMPORTANT
A rifle bullet is photographed in flight using two flashes of light separated by a time interval of (1.00±0.02)ms. The first image of the bullet on the photograph appears to be at a position of (22.5±0.5)cm on a scale underneath the flight path. The position of the second image is (37.5±0.7)cm on the same scale. Find the speed of the bullet and its absolute uncertainty.