The perfect elastic Collision ball will hit the door first because the clay is heavier and will take more time
Answer:

Explanation:
Mass of block=10 kg
Applied horizontal force =F=20 N
Friction force=f=10 N
We have to find the acceleration of block.
Net force=Applied horizontal force-friction force

Where F= Horizontal force
f=Friction force
m=Mass of object
a=Acceleration of object


Hence, the acceleration of the block=
Answer:
U = 80.91 J
Explanation:
In order to calculate the electric potential energy between the three charges you use the following formula:
(1)
k: Coulomb's constant = 8.98*10^9Nm^2/C^2
q1: q2 charge
r1,2: distance between charges 1 and 2.
For the three charges you have:
(2)
You use the fact that q1=q2=q3=q and that the distance between charges are equal. Then, in the equation (2) you have:
q = 1.45μC = 1.45*10^-6C
r = 0.700mm = 0.700*10^-3m

The electric potential energy between the three charges is 80.91 J
2.5m/s
Explanation:
Given parameters:
Initial velocity = 0m/s
Acceleration = 0.5m/s²
time of travel = 5s
Solution:
Final velocity = ?
Solution:
Acceleration can be defined as the change in velocity with time:
Acceleration = 
From the equation above, the unknown is final velocity:
Final velocity - initial velocity = Acceleration x time
since initial velocity = 0
Final velocity = 0.5 x 5 = 2.5m/s
Learn more:
Acceleration brainly.com/question/3820012
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