Acceleration can be defined as the change of speed in an instant of time, that is

Here,
Final velocity
Initial velocity
Change in time
From this expression we will calculate the requested values replacing the variables in each of the given terms
PART A) The values under this condition are:



Replacing,


PART B ) The values under this condition are:



Replacing,


Therefore the acceleration in the second time interval is
PART C) The values under this condition are:



Replacing,


Answer:
0.00712 m
Explanation:
Given:
Charge on first particle (q₁) = 75 nC = 
Charge on second particle (q₂) = 75 nC = 
Force (F) = 1.00 N
Separation (d) = ?
The magnitude of force is given by Coulomb's law which states that, the magnitude of force acting between two charged particles separated by a distance is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them.
Therefore, the magnitude of force is given as:

Where,
is the coulomb's constant.
Plug in the given values and solve for 'd'. This gives,

Therefore, the distance between the charges is 0.00712 m.
Answer:
L = ¼ k g / m
Explanation:
This is an interesting exercise, in the first case the spring bounces under its own weight and in the second it oscillates under its own weight.
The first case angular velocity, spring mass system is
w₁² = k / m
The second case the angular velocity is
w₂² = L / g
They tell us
w₂ = ½ w₁
Let's replace and calculate
√ (L / g) = ½ √ (k / m)
L / g = ¼ k / m
L = ¼ k g / m
Newtons first law of motion or friction
Answer:
( 1000 × 4 = 4,000) (800×3= 2400) (800×2=1600) the answer is 1600 hope it helps