Practical questions

You will complete 12 Specified Practical Activities if you are studying GCSE Physics. You could be asked questions about the apparatus, methods, safety precautions, results, analysis and evaluation of these experiments.

Questions courtesy of Eduqas.

Sample question 1 - Foundation

Question

One way of analysing motion in a physics lab is to use ticker tape.

A long tape is attached to a moving trolley and threaded through a device that places a tick upon the tape at regular intervals of time.

The movement of a trolley down a slope was investigated using ticker tape with a frequency of 50 Hz. The ticker tape produced 50 dots per second.

The 14 cm length of the ticker tape was cut into four strips. It was cut through the middle of the first and then the sixth hole.

A strip of ticker tape, the length is labelled, and it is split into four sections, each bigger than the last. Three are labelled, and each section has the same number of dots.Bar chart plotting ticks against length in centimetres. Four bars, each getting consecutively bigger. The first and last bar are labelled on the x-axis.The four cut lengths of ticker tape are shown above

a) i) What is meant by acceleration? [1 mark]

ii) How would the appearance of ticker tape be different if the trolley moved at constant velocity? [1 mark]

iii) Calculate the time that it took for each strip to form and hence show that the mean velocity of the trolley in the strip marked A was 20 cm/s. [2 marks]

b) The mean velocity of the trolley in strip B was 30 cm/s. Recall a suitable equation to calculate the acceleration of the trolley in cm/s2. [3 marks]

a) i) Rate of change of velocity [1]

ii) Holes evenly spaced/same distance between holes/same length strips [1]

iii) Time for each strip = 5 × 1/50th s = 0.1 s [1]

velocity = displacement ÷ time = 2 ÷ 0.1 = 20 cm/s [1]

b) a  = (v  -  u)  \div  t [1]

So, a  =  (30 - 20)  \div  0.1 =  10  \div  0.1  =  100~cm/s^2 [2]

Sample question 2 - Higher

Question

A student sets up a glider on a frictionless air track. Light gates are set up to measure its acceleration. A frictionless pulley is attached to the end of the air track as shown, allowing a force to be applied to the glider.

Glider on an air track, this is attached to a pulley and a weight with a force acting downward. There are also two light gates on the air track.

From the results taken, a graph is plotted showing the relationship between the force and the acceleration of the glider.

Graph plotting force in newtons against acceleration in meters per second squared. Line is directly proportional.

a) Recall an equation to calculate the mass of the glider. [2 marks]

b) A force of 2.0 N is used to pull the glider from rest.

i) Determine the value of the acceleration. [1 mark]

ii) The string snaps at 0.6 s. Use your value of acceleration and recall equations to calculate the momentum of the glider at this time. [4 marks]

iii) Explain whether or not this momentum changes as the glider continues along the track, before reaching the end. [2 marks]

a) Use any pair of coordinates and F  =  ma [1]

1.2  =  m  \times  1.5

m  =  0.8 \ kg [1]

b) i) F  =  ma

2  =  0.8 \times a

a  =  2  \div  0.8 = 2.5~m/s^2 [1]

ii) a  = (v  -  u)  \div  t

2.5  =  (v  -  0)  \div  0.6 [1]

v  =  2.5  \times  0.6  =  1.5~m/s [1]

momentum  =  m  \times  v [1]

=  0.8  \times  1.5  =  1.2~kg~m/s [1]

iii) The momentum does not change [1] as there is no resultant force acting on the trolley. [1]