You have placed a cube of ice in a cup of water based on the graph answer the questions that follow: graph attached.
1. when has the ice melted?
2. what temperature does the phase change occur?
3. at 25° c what is the state or states of the water in the beaker?
4. at nine minutes what is the state or states of the water in the beaker?
5. what did you observe about the temperature of the water inside the beaker when ice is still present?
6. explain why sublimation and deposition are classified as a physical change

During physical science, ms. greene challenged her students to produce an energy transformation. james and jill wrapped a 4-inch nail with a coil of fifty turns of wire. they connected one end of the coil to one terminal of a knife switch. they connected the other terminal of the knife switch to the battery. finally, they connected the end of the coil to the other terminal of the battery. james held the tip of a 1-inch nail near the flat end of the 4-inch nail. jill closed the knife switch quickly and then opened it. the 1-inch nail was pulled toward the 4-inch nail. what is the best explanation of why the nail moved? a) electrical energy was converted to mechanical energy in the 1-inch nail. b) the 4-inch nail became an electromagnet and the magnetic force attracted the 1-inch nail. c) the electric current in the 4-inch nail was converted to mechanical energy in the 1-inch nail. d) the 4-inch nail had a positive charge and the 1-inch nail had a negative charge. opposites attracted.

Blank liquids and gases exert a buoyant force on objects placed in them

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?