2km*1000=2000m
S=ut+1/2at^2
a=0,thus s=ut
2000=90t
t=2000/90
=22.22s(to 4 s.f)
Please mark as brainliest
Answer:
Matthias Schleidan
Explanation:
because Matthias Schleiden found that all plants are composed of cells, and communicated the finding to Schwann, who had found similar structures in the cells. Other researchers confirmed the similarity, as explained in his book, where he concluded, "All living things are composed of cells and cell products.
This became the cell theory.
I learn that in my old school.
Answer:
(1) 2.25m/s^2
(2) 45.6m
Explanation:
(1) A car accelerates uniformly from 12m/s to 39m/s in 12 seconds
Therefore the average acceleration can be calculated as follows
a = 39-12/12
a = 27/12
a= 2.25m/s^2
(2) A butterfly is flying at 4m/s , it accelerates uniformly at 1.2 m/s for 6 seconds
u= 4
a= 1.2
t= 6
Therefore the distance can be calculated as follows
S= ut + 1/2at^2
= 4×6 + 1/2 × 1.2 × 6^2
= 24 + 1/2 × 1.2 × 36
= 24 + 1/2 × 43.2
= 24 + 21.6
S = 45.6m
Hence the butterfly travels at 45.6m
Answer:
= 1,386 m / s
Explanation:
Rocket propulsion is a moment process that described by the expression
- v₀ = 
ln (M₀ / Mf)
Where v are the velocities, final, initial and relative and M the masses
The data they give are the relative velocity (see = 2000 m / s) and the initial mass the mass of the loaded rocket (M₀ = 5Mf)
We consider that the rocket starts from rest (v₀ = 0)
At the time of burning half of the fuel the mass ratio is that the current mass is
M = 2.5 Mf
- 0 = 2000 ln (5Mf / 2.5 Mf) = 2000 ln 2
= 1,386 m / s
