Nervous coordination (A-level only)

Two researchers investigated the reflex response time to a brief localized mechanical touch stimulus on the foot using a vertical drop-rod apparatus.

Participant P sat with their eyes closed and their foot resting above the base of a vertical slider rail.
Researcher Q held a weighted rod vertically, with the $mm0\text{ mm}$ mark aligned with the top of a mechanical trigger on Participant P's foot.
Researcher Q released the rod without warning.
As soon as Participant P felt the touch stimulus, they pressed a rapid-response handheld button to lock the slider and stop the rod.
The distance the rod had fallen before being locked was recorded to the nearest millimeter.

The test was repeated four times. Table 1 shows the results.

Table 1

Trial	Distance the rod fell / $mm\text{mm}$
1	125
2	117
3	118
4	15

The researchers converted these distances into reaction times using calibration data in Table 2.

Table 2

Distance the rod fell / $mm\text{mm}$	Reaction time / $ms\text{ms}$
50	101
60	111
70	120
80	128
90	135
100	142
110	148
120	154
130	159
140	164

Calculate the percentage uncertainty in the measurement of Trial 1 in Table 1, assuming an absolute uncertainty of $mm\pm 2\text{ mm}$ . Give your answer to two decimal places.

Participant P estimated that the total length of the sensory and motor nerve pathway involved in this reflex arc was $m2.31\text{ m}$ . Calculate the mean speed of nerve impulse transmission. Do not use the anomalous value (Trial 4) in your calculation. Give your answer to three significant figures.

Two researchers investigated the reflex response time to a brief localized mechanical touch stimulus on the foot using a vertical drop-rod apparatus.

Participant P sat with their eyes closed and their foot resting above the base of a vertical slider rail.
Researcher Q held a weighted rod vertically, with the $mm0\text{ mm}$ mark aligned with the top of a mechanical trigger on Participant P's foot.
Researcher Q released the rod without warning.
As soon as Participant P felt the touch stimulus, they pressed a rapid-response handheld button to lock the slider and stop the rod.
The distance the rod had fallen before being locked was recorded to the nearest millimeter.

The test was repeated four times. Table 1 shows the results.

Table 1

Trial	Distance the rod fell / $mm\text{mm}$
1	125
2	117
3	118
4	15

The researchers converted these distances into reaction times using calibration data in Table 2.

Table 2

Distance the rod fell / $mm\text{mm}$	Reaction time / $ms\text{ms}$
50	101
60	111
70	120
80	128
90	135
100	142
110	148
120	154
130	159
140	164

Calculate the percentage uncertainty in the measurement of Trial 1 in Table 1, assuming an absolute uncertainty of $mm\pm 2\text{ mm}$ . Give your answer to two decimal places.

Question 1

Nervous coordination (A-level only)

Question 1

Nervous coordination (A-level only)

Question 1

Nervous coordination (A-level only) Questions

Nervous coordination (A-level only)

Question 1

Nervous coordination (A-level only) Questions