Answer:
The percentage uncertainty in the average speed is 0.10% (2 sig. fig.)
Explanation:
Consider the formula for average speed
.
,
where
is the total distance, and
is the time taken.
The percentage uncertainty of a fraction is the sum of percentage uncertainties in
- the numerator, and
- the denominator.
What are the percentage uncertainties in
and
in this question?
The unit of the absolute uncertainty in
is meters. Thus, convert the unit of
to meters:
.
.
The unit of the absolute uncertainty in
is seconds. Convert the unit of
to seconds:

Similarly,
.
The average speed
here is a fraction of
and
. Both
and
come with uncertainty. The percentage uncertainty in
will be the sum of percentage uncertainties in
and
. That is:
.
Generally, keep
- two significant figures for percentage uncertainties that are less than 2%, and
- one for those that are greater than 2%.
The percentage uncertainty in
here is less than 2%. Thus, keep two significant figures. However, keep more significant figures than that in calculations to make sure that the final result is accurate.
He would have potential, he hasn’t gone down the mountain yet so he remains potential
Gravity increases as mass increases.
Gravity decreases when distance decreases
I hope I help.
If both waves have the same wavelength, then the amplitude of
their sum could be anything between 1 cm and 9 cm, depending
on the phase angle between them.
If the waves have different wavelengths, then the resultant is a beat
with an amplitude of 9 cm.