two ice skaters push each other, and move in opposite directions. the mass of one is 75 kg, and his speed is 2 m/s. if the mass of the other is 30 kg, what is her speed?

In which medium does sound travel the fastest? A. salt water B. fresh water C. air * ** D. cast iron A wave has a wavelength of 10 mm and a frequency of 5 hertz. What is its speed? A. 50 mm/s B. 50 hertz/s C. 2 mm/s 0.

When a passenger in train A looks at a passenger directly across in train B it appears that train B is not moving even though both trains are moving. How does the speed od train A compare to train B

Which of the following is the most likely end for a star that formed from an extremely large nebula? Black hole Main sequence Planetary nebula White dwarf

Recessive Disorder or Disease - How would a child get it?

As water begins to boil in a kettle the hotter water at the bottom of the kettle closest to the stove begins to rise and the cooler water above sinks and warms. Why does this occur?

Which actions are evidence that a chemical reaction has occurred? Check all that apply. A: a change in color B: the formation of a precipitate C: a clear liquid becoming cloudy D: a change in shape E: the formation of bubbles F: the formation of

Which sphere forms Earth's outermost layer? Atmosphere Biosphere Cryosphere Hydrosphere

an 100kg object traveling at 50m/s collides (perfectly inelastic) with a 50kg object initially at rest. what is the sum of the momentum of both objects prior to the collision?

A train moves at constant velocity of 50km/h. how far will it move in 0.5h?

Which process best describes part of a scientific investigation? O designing a solution O evaluating the conclusion O evaluating the solution O identifying the conclusion