Answer:
whats the question... you didn't put the question up
Answer: B.move from the negatively charged body to the positively charged body.
Explanation: If one body is positively charged and another body is negatively charged, free electrons tend to move from the negatively charged body to the positively charged body. This happens because they have different charges and therefore electrons are more attracted to the positive or its opposite charge.
Answer:
increased by 9 times
Explanation:
As the period of a simple pendulum is defined as the following formula
where L is the length of the pendulum and g is the constant gravitational acceleration. Since L is under a square root, if you want to triple the period of vibration, L must be increased by 9 times so that 
Answer:
318.3 nm
Explanation:
We approximate the circular film as a cylinder of height h and radius, r. Its volume V = πr²h. Since this volume equals the volume of the oil drop, the height of the circular film is thus h = V/πr²
V = 10⁻¹⁰ m³ and r = 10 m
Substituting into h, we have
h = 10⁻¹⁰ m³/π(10)²
= 0.3183 × 10⁻¹² m
= 3183 × 10⁻⁹ m
= 318.3 nm
