A student rubs a glass rod with a piece of silk to charge it. He then touches it to a metal sphere hung from a string. Which statement correctly describes what
happens?
a) The metal sphere will be attracted to the glass rod after it is touched.
b) The metal sphere will be repelled by the glass rod after it is touched.
c) The metal sphere will have a negative charge after the glass rod touches it.
d) The metal sphere becomes neutral once the glass rod is removed.

Study the following reaction carefully. what classification should this reaction have? 4al + 3o2 2al2o3synthesisdecompositionsingle replacementdouble displacement

While goofing off at the ice skating rink, a student takes off her shoes and places each of them on the ice. her friend, a hockey player, then shoots a hockey puck at each shoe. the first puck immediately comes to rest after it collides with the left shoe. the second puck rebounds after it collides with the right shoe. if each hockey puck has the same incoming speed, which shoe has greater speed after the collision? the right shoe. both shoes have the same speed. the left shoe.

In a stagnant pool of water, a crayfish may spend much of its time lying with one side of its carapace near the surface of the water. in this position, it will move the walking legs on that side in a rhythmic back-and-forth motion. explain the likely function of this behavior.