Answer:
The answer to your question is
a) t = 2.55 s
b) t = 5.5 s
Explanation:
Data
vo = 25 m/s
h = 2 m
g = 9.81 m/s
Formula
t = -(vo)/g
a)
t = -(25)/9.81
t = 2.55 s
b)
Tt = 2t
Tt = 2(2.55)
Tt = 5.1 s
Time in the last 10 m
10 = 25t + (1/2)(9.81)t²
Simplify
10 = 25t 4.91t²
4.9t² + 25t - 10 = 0
Solve the equation using an online calculator
t₁ = 0.37 s t₂ = -5.47 s
The correct answer is t₁, t₂ is incorrect because there are no negative answers.
Total time = 5.1 + 0.37
= 5.5 s
A.
Kinematics is independent of mass, in most cases.
Let us assume that rocket only runs in initial energy and not using its own to flying.
Also , let upward direction is +ve and downward direction is -ve .
Initial velocity , u = 58.8 m/s .
Acceleration due to gravity ,
.
Final velocity , v - = 0 m/s .
We know , by equation of motion .

Hence, this is the required solution .
Explanation:
It is given that,
Initially, the jogger is at rest u₁ = 0
He accelerates from rest to 4.86 m, v₁ = 4.86 m
Time, t₁ = 2.43 s
A car accelerates from u₂ = 20.6 to v₂ = 32.7 m/s in t₂ = 2.43 s
(a) Acceleration of the jogger :


a₁ = 2 m/s²
(b) Acceleration of the car,


a₂ = 4.97 m/s²
(c) Distance covered by the car,


d₁ = 5.904 m
Distance covered by the jogger,


d₂ = 64.73 m
The car further travel a distance of, d = 64.73 m - 5.904 m = 58.826 m
Hence, this is the required solution.
A proton (+).
It is the opposite to an electron.