Answer:
The charge on the ball bearing 4.507 × 10^-8 C
Explanation:
From Coulomb's law
F = kq1q2/r²
make q2 the subject
q2 = Fr²/kq1
q2 = (1.8×10^-2 × 0.026²) ÷ (9×10^9 × 30×10^-9)
q2 = 4.507 × 10^-8 C
When she reaches the top, she has more potential energy than she had at the bottom.
Potential energy = (mass) x (gravity) x (height)
= (40 kg) x (9.8 m/s²) x (5 m)
= 1,960 more joules .
Power = (energy) / (time)
= (1,960 joules) / (7 seconds)
= 280 watts
(about 0.375 horsepower)
Answer:
Where the electric potential is constant, the strength of the electric field is zero.
Explanation:
As a test charge moves in a given direction, the rate of change of the electric potential of the charge gives the potential gradient whose negative value is the same as the value of the electric field. In other words, the negative of the slope or gradient of electric potential (V) in a direction, say x, gives the electric field (Eₓ) in that direction. i.e
Eₓ = - dV / dx ----------(i)
From equation (i) above, if electric potential (V) is constant, then the differential (which is the electric field) gives zero.
<em>Therefore, a constant electric potential means that electric field is zero.</em>
<span>These Russian nesting dolls are a good analogy for the strongest magnet in the world, because the magnitis were put inside each other. The magnets would be fitted together. Because they are closer together, the coils of magnet would be stronger. They would be able to magnetize better.</span>
Answer:
push up agaisnt you with equal force.
