B a bar magnet has a north and a south pole.
Average speed = total distance / total time
total distance = 40 + 20 = 60km
total time taken = 10 + 5 = 15 minutes
Average speed = 60/15 = 4km/min
data which is expressed in form of following way
here in above expression
= true value
= uncertainty in the value
now the relative uncertainty is given as
now by above formula we can say
a) 2.70 ± 0.05cm
here
True value = 2.70
uncertainty = 0.05
Relative uncertainty = = 0.0185
b) 12.02 ± 0.08cm
here
True value = 12.02
uncertainty = 0.08
Relative uncertainty = = 0.00665
maximum allowed value of the speed in roller coaster is given as
now from kinematics we can say
here initial speed will be
acceleration is due to gravity
now we can use this to find the height
so maximum allowed height will be 20.4 m