Answer:
Lifting force, F = 21240 N
Explanation:
It is given that,
Mass of the helicopter, m = 1800 kg
It rises with an upward acceleration of 2 m/s². We need to find the lifting force supplied by its rotating blades. It is given by :
F = mg + ma
Where
mg is its weight
and "ma" is an additional acceleration when it is moving upwards.
So, 
F = 21240 N
So, the lifting force supplied by its rotating blades is 21240 N. Hence, this is the required solution.
Answer:
The initial acceleration of the 59g particle is
Explanation:
Newton's second laws relates acceleration (a), net force(F) and mass (m) in the next way:
(1)
We already know the mass of the particle so we should find the electric force on it to use on (1), the magnitude of the electric force between two charged objects by Columb's law is:

with q1 and q2 the charge of the particles, r the distance between them and k the constant
. So:

Using that value on (1) and solving for a

Answer:
100 Degrees is boiling point.
Explanation:
Answer:
D. two positively charged objects
The water molecules with a slower speed are escaping