HELP Ana and Dana were at the beach enjoying the waves. Remembering what they learned in science class, Ana said that the ocean waves were mechanical waves, but Dana said they were electromagnetic waves. Which student is correct and why? (AKS 9b, DOK 2)

A.

Both of them are right. Ocean waves travel through a medium so it is a mechanical wave. It is also an electromagnetic wave since the particles moves up and down.

B.

Only Ana is right. Ocean waves travel must have a medium to travel through so it is a mechanical wave.

C.

Only Dana is right. In ocean waves the particles move up and down which is the characteristic of an electromagnetic wave. Ocean waves need a medium so it is not a mechanical wave.

D.

Both of them are wrong. Neither ocean waves nor EM waves need a medium.

James is trying to prove newton's 2nd law of motion. he tries to move four different objects with different masses, shapes, and sizes from point a to point b. the objects are a toy car, a car, a refrigerator, and a kitchen table. after some experimentation, he finds that force is dependent on the mass of the object, rather than it's size or shape. the object that takes the most force to move is the

While studying chemical reactions and conservation of matter, sarah's class conducted a variety of experiments. sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. the students lit the candle and let it burn to completion. all that was left was wax and charred candle wick. per their teacher's instructions, the students found the mass of the products. their data can be seen in the data table. formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter. a) the students could repeat the experiment using different candles; there might have been a flaw in the candle. b) the experiment should be repeatable. the students should run several trials and then take an average of the after mass in each trial. c) the students should have someone in the class check their measurement skills as they repeat the experiment. they may have made an error using the balance. d) the students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed. submit

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy