Answer:
= 38.89 m/s
Explanation:
speed of first car (u) = 80 km/h = 22.22 m/s
time (t) = 30 s
distance (d) = 500 m
find the speed of second car (v)
let the speed of the second car be represented as 'v'
We can get the speed of the second car from the formula net speed = distance between cars / time interval
where
- distance between cars = 500 m
- time interval = 30 s
- net speed = v-22.22 (since both cars move in the same direction)
- substituting the above into the formula we have
v-22.22 = 500 / 30
v = 500/30 + 22.22
v = 38.89 m/s
In this item, there needs to be a basis as to how many significant numbers can be present in a certain figure. If the answer 327.66 m/s is to be expressed as a 3 significant figures only, the answer would have to be 328. What was done here is to simply round up the units digit of the number since the decimal place (tenths) digit has a value of greater than 4.
The answer to this item is therefore letter B.
Answer:
33.0 m
Explanation:
We are given that
Wavelength,
Diameter of pupil=d=5.1 mm=
By Rayleigh criteria
Substitute the values