Empty spaces are referred to as

Which scientist explained that the lines in the spectrum reflect the energy changes of electrons for an element's atom when an electron jumps from an orbital of higher energy to one of lower energy? A. John Dalton B. Ernest Rutherford C. J. J.

Universal law in effect at all times?

Which of the following is an inclined plane? - Stairs - Wheelchair ramp - Sloping driveway - Road going up a mountain

Is gravity internal force or external force?

Uranus was the first planet predicted by mathematics to exist before it was actually observed in a telescope Select one: True False

Why does a balloon filled with helium rise while a balloon filled with an equal volume of average atmospheric air does not? A. Helium has no mass, but air does. B. Helium increases the balloon's mass more than air. C.

Consider the following controls in an automobile in motion : gas pedal, brake, steering wheel. what are the controls in this list that cause an acceleration of the car?

What material are oil pipelines made from?

3/129 A 175-lb pole vaulter carrying a uniform 16-ft, 10-lb pole approaches the jump with a velocity v and manages to barely clear the bar set at a height of 18 ft. As he clears the bar, his velocity and that of the pole are essentially zero.

A few years ago, Serena Williams dived to hit a tennis ball right after it bounced off the ground. The ball bounced on the ground 10.3 m from the net, and after Serena hit the ball it flew over the 0.