Answer:
it would take rod B twice as much time
Explanation:
it would take rod B twice as much time as it is twice as thick and twice as long. Due to this reason it would take the electric charge not only more time but even more voltage to travel through the rod
Answer:

Explanation:
We know that charge on electron

r= 2 nm
We know that force between two charge given

Now by putting the value


We know that mass of electron
The mass of electron

F= m a
a= Acceleration of electron
a= F/m


initial velocity given that zero ,u=0


Answer:
Total displacement will be 47 meter
Total distance will be 83 meters
Explanation:
We have given that first the student go eastward towards bus stop 20 meters
But he realizes that she dropped his physics notebook and so h=she turns back along the same way up to 18 meters
So displacement = 20-18 = 2 meters
And he travel 45 meters in east along the bus stop so total displacement = 45+2 = 47 meters
Total distance traveled by the student = 20+18+45 = 83 meters
Use the law of universal gravitation, which says the force of gravitation between two bodies of mass <em>m</em>₁ and <em>m</em>₂ a distance <em>r</em> apart is
<em>F</em> = <em>G m</em>₁ <em>m</em>₂ / <em>r</em>²
where <em>G</em> = 6.67 x 10⁻¹¹ N m²/kg².
The Earth has a radius of about 6371 km = 6.371 x 10⁶ m (large enough for a pineapple on the surface of the earth to have an effective distance from the center of the Earth to be equal to this radius), and a mass of about 5.97 x 10²⁴ kg, so the force of gravitation between the pineapple and the Earth is
<em>F</em> = (6.67 x 10⁻¹¹ N m²/kg²) (1 kg) (5.97 x 10²⁴ kg) / (6.371 x 10⁶ m)²
<em>F</em> ≈ 9.81 N
Notice that this is roughly equal to the weight of the pineapple on Earth, (1 kg)<em>g</em>, where <em>g</em> = 9.80 m/s² is the magnitude of the acceleration due to gravity, so that [force of gravity] = [weight] on any given planet.
This means that on this new planet with twice the radius of Earth, the pineapple would have a weight of
<em>F</em> = <em>G m</em>₁ <em>m</em>₂ / (2<em>r</em>)² = 1/4 <em>G m</em>₁ <em>m</em>₂ / <em>r</em>²
i.e. 1/4 of the weight on Earth, which would be about 2.45 N.