Answer:
A) F=-20.16×10⁹N
B) if the distance doubles, force is 4 times smaller.
Explanation:
q1=-28C
q2=5mC=0.005C
d=25cm=0.25m
Electrostatic force between charges: F=k×q1×q2/d², where k is a coefficient that has the value k=9 × 10⁹ N⋅m²⋅C^(-2) for air.
Thus:
F=9×10⁹×(-28)×0.005/0.25²
F=-20.16×10⁹N
The minus sign indicates attraction.
If distance doubles, d1=2×d, then we have 4d² at the denominator and the force is 4 times smaller.
Answer:
v = 6.95 m/s
Explanation:
Given that,
A diver is on a board 1.80 m above the water, s = 1.8 m
The initial speed of the diver, u = 3.62 m/s
Let v is the speed with which she hit the water. It will move under the action of gravity. Using the equation of motion as follows :

So, she will hit the water with a speed of 6.95 m/s.
Gravitational to Kinetic to Chemical
Answer:
I think its 12 cm itself. Because in the question it is said that the length is same in all temperature