Answer:
Part a)
a = -9.81 m/s/s
Part b)
v = 0
Part c)
v = 9.81 m/s
Part d)

Explanation:
Part a)
During the motion of ball it will have only gravitational force on the ball
so here the acceleration of the ball is only due to gravity
so it is given as

Part b)
As we know that ball is moving against the gravity
so here the velocity of ball will keep on decreasing as the ball moves upwards
so at the highest point of the motion of the ball the speed of ball reduce to zero

Part c)
We know that the total time taken by the ball to come back to the initial position is T = 2 s
so in this time displacement of the ball will be zero



Part d)
at the maximum height position we know that the final speed will be zero
so we will have

here we have


Answer:
(a) 62.5 m
(b) 7.14 s
Explanation:
initial speed, u = 35 m/s
g = 9.8 m/s^2
(a) Let the rocket raises upto height h and at maximum height the speed is zero.
Use third equation of motion


h = 62.5 m
Thus, the rocket goes upto a height of 62.5 m.
(b) Let the rocket takes time t to reach to maximum height.
By use of first equation of motion
v = u + at
0 = 35 - 9.8 t
t = 3.57 s
The total time spent by the rocket in air = 2 t = 2 x 3.57 = 7.14 second.
Answer:
F = 1.19 x 10⁹ N
Explanation:
The electrostatic force between the charged particles is given by Colomb's Law as follows:

where,
F = Electrostatic force = ?
k = Colomb's constant = 9 x 10⁹ N.m²/C²
q₁ = q₂ = charge on proton = 1.6 x 10⁻¹⁹ C
r = distance between protons = 4.4 x 10⁻¹⁰ m
Therefore,

<u>F = 1.19 x 10⁹ N</u>
It depends on what robots are in our future. Robots could even be the future.