Answer:
d) F
Explanation:
According to columb's law:
"The magnitude of electrostatic force between two charges is directly proportional to the product of magnitude of two charges and inversly proportional to separation between them."
If q₁ and q₂ are magnitude of two charges, d is distance between them and k is dielectric constant, then force F is given by
According to this force exerted on point charge Q is same as that of 3Q, so force point 3Q charge experience is also F
Answer:
m = 12.05 kg
Explanation:
Spring constant in K, N/m
K = 200/10* 100
K = 2000 N/m
Angular Frequency = sqrt (Spring constant / (Mass )
ω = 2 π f
ω = 2π* 2.05 Hz = 12.8805 rad/s
ω^2 = Spring constant / Mass
Mass= Spring constant / ω^2
ω^2 = 165.907 rad^2/s^2
m = 2000 (N/m)/165.907 (rad^2/s^2)
m = 12.05 kg
Answer:
The kinetic energy of the more massive ball is greater by a factor of 2.
Explanation:
By conservation of energy, we know that the initial energy = final energy. At first, the balls are dropped from a height with no initial velocity so their initial energy is all potential energy. When they reach the bottom, all their energy is kinetic energy. So all of their energy is changed from potential to kinetic energy. This means that the ball with greater potential energy will have a greater kinetic energy.
Potential energy = mgh. Since g = gravity is a constant and h = height is the same, the only difference is mass. Since mass is directly proportional to potential energy, the greater the mass, the greater the potential energy, so the more massive ball has a greater initial potential energy and will have a greater kinetic energy at the bottom.
Additionally, let B1 = lighter ball with mass m and let B2 = heavier ball with mass m2. Since we know that intial potential energy = final kinetic energy. We can rewrite it as potential energy = kinetic energy = mass * gravity constant * height. For B1, it is mgh and for B2 it is 2mgh, so B2's kinetic energy is twice that of B1.
Answer:
168 seconds (2 min 48 s)
Explanation:
Find the heat absorbed by the water.
q = mCΔT
q = (1 kg) (4200 J/kg/K) (70°C − 40°C)
q = 126,000 J
Power is energy per time.
P = q / t
750 W = 126,000 J / t
t = 168 s
It takes 168 seconds (2 min 48 s).
Determined by cross product or ( vector product )
