Answer:
F' = (4/9)F
Explanation:
The electrostatic force between two charged objects is given by Coulomb's Law:
F = kq₁q₂/r² -------------------- equation (1)
where,
F = Electrostatic Force
k = Coulomb's Constant
q₁ = magnitude of first charge
q₂ = magnitude of second charge
r = distance between charges
Now, when the charges and distance altered as follows:
q₁' = 2q₁
q₂' = 2q₂
r' = 3r
Then,
F' = kq₁'q₂'/r'²
F' = k(2q₁)(2q₂)/(3r)²
F' = (4/9)kq₁q₂/r²
using equation (1):
<u>F' = (4/9)F</u>
Convert the given in SI units.
(44 ft/sec)(1 m/ 3.28 ft) = 13.41 m/sec
The distance traveled and the initial velocity can be related through the equation,
d = (Vf)² - (Vi)²/ 2a
where d is the distance, Vf is the final velocity, Vi is the initial velocity, a is the acceleration due to gravity. Substituting the known values from the given above,
d = ((0 m/s)² - (13.41 m/s)²)/ 2(-9.8 m/s²)
The value of d from the equation,
d = 9.17 meters
Convert this to feet,
d = (9.17 m)(3.28 ft / 1 m) = 30 ft
Answer: 30 ft
Answer: D
Explanation:
When an object falls gravity is pulling down on it and is picking up speed, but as it gains speed air resistance becomes a faster. Air resistance increases with speed. And that force keeps it from accelerating eventually the object will pick up speed such that the force due to air resistance will keep it from getting any more speed at that point force due to air resistance is equal to its weight (mg) and the net force is equal to zero so it won’t accelerate any more at that point it is said to be moving in terminal velocity.
When an object has reached terminal velocity, it will have a constant velocity
Answer:
option B
Explanation:
When you rub a clear plastic pen with the wool the plastic pen gets charges this phenomenon is known as frictional charging.
Due to rubbing, the pen gets negatively charged.
We know, opposite charge attract each other and the same charge repel each other.
So, when the pen is negatively charged the tape might be positively charged or the tape might be uncharged.
Hence, the correct answer is option B
Answer:
distance = 6 m
Explanation:
- Distance is a scalar quantity (so, only magnitude, no direction), and it is calculated as the scalar sum of all the distances travelled by an object during its motion, regardless of the direction. So, in this problem, the distance covered by the pinecone is
d = 4 m + 2 m = 6 m
- Displacement is a vector quantity (magnitude+direction), and its magnitude is calculate as the distance in a straight line between the final position and the initial position of the object. In this case, the final position is 2 m west and the initial position is 0 m, so the displacement of the pinecone is
d = 2 m west - 0 m = 2 m west
So, a scalar quantity from this scenario is
distance = 6 m