Answer:
negative, positive
Explanation:
A we know that the electrons have a negative charge.
So, when a body has some excess electrons, it means it has negative charge.
When a body has an deficiency of eletrons, it means it gains a positive charge.
An area with excess electrons has a net _<u>negative</u>__ charge; an area with a deficit of electrons has a net _<u>Positive</u>____ charge.
Answer:
I am not a driver, but I think it's C.
Explanation:
The speed of the man and the chair after the book is thrown is 0.2 m/s.
The given parameters:
- <em>mass of the book, m₁ = 2.1 kg</em>
- <em>speed of the book, u₁ = 7.2 m/s</em>
- <em>mass of the man, M = 70 kg</em>
- <em>mass of the book, m = 9.2 kg</em>
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The total mass of the man and the book is calculated as follows;
m₂ = 70 kg + 9.2 kg
m₂ = 79.2 kg
The speed of the man and the chair after the book is thrown is determined by applying the principle of conservation of linear momentum;

Thus, the speed of the man and the chair after the book is thrown is 0.2 m/s.
Learn more about conservation of linear momentum here: brainly.com/question/7538238
Answer:
less than 20580 N
Explanation:
According to the newton's second law of motion
Force = mass * acceleration
(assuming gravitational acceleration =9.8 m/s2 )
acceleration = 30*9.8 = 294 m/s2
acting Force = 70 * 294
= 20580 N
Since the acceleration was less than 30g , acting force should also be less than 20580 N
Answer
According the conservation of energy

I for ball = 




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a) 


b) 

