What do they look like? Tree swallows are small birds (about 14 cm long) with long wings and small legs and feet. They are irridescent greenish-blue on their head, shoulders and back, and white their chin, breast and belly. Tree swallows have a short black beak and dark brownish feet.
Ernest Rutherford concluded that an atom contains a very small, dense center, called a nucleus, with a positive charge as a result of his gold foil experiment.
-Because the charged rod doesn't touch the sphere, no charge is added to or removed from the sphere. Instead, the rod attracts some of the sphere's negative charge to the side of the sphere near the rod. This leaves a deficit of negative charge on the opposite side of the sphere, so that side is now positively charged. The negative charge on the sphere is close to the rod so it is strongly attracted to the rod. The positively charge on the sphere is far from the rod, so it is weakly repelled by the rod.