As we know that two charges exert force on each other when they are placed near to each other
The force between two charges is given as

here we know that
= two different point charges
r = distance between two point charges
also we know that two similar charges always repel each other while two opposite charges always attract each other
so here correct answer would be
<em>A. A positive and negative charge attract each other.</em>
Answer:
The time it takes the proton to return to the horizontal plane is 7.83 X10⁻⁷ s
Explanation:
From Newton's second law, F = mg and also from coulomb's law F= Eq
Dividing both equations by mass;
F/m = Eq/m = mg/m, then
g = Eq/m --------equation 1
Again, in a projectile motion, the time of flight (T) is given as
T = (2usinθ/g) ---------equation 2
Substitute in the value of g into equation 2

Charge of proton = 1.6 X 10⁻¹⁹ C
Mass of proton = 1.67 X 10⁻²⁷ kg
E is given as 400 N/C, u = 3.0 × 10⁴ m/s and θ = 30°
Solving for T;

T = 7.83 X10⁻⁷ s
D = 1/2 g t^2. It works out to 44.1 meters.
Explanation:
The force of the roller-coaster track on the cart at the bottom is given by :
, m is mass of roller coaster
Case 1.
R = 60 m v = 16 m/s

Case 2.
R = 15 m v = 8 m/s

Case 3.
R = 30 m v = 4 m/s

Case 4.
R = 45 m v = 4 m/s

Case 5.
R = 30 m v = 16 m/s

Case 6.
R = 15 m v =12 m/s

Ranking from largest to smallest is given by :
F>E>A=B>C>D
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