Why is it important in a friction experiment of force, that a string pulling a block is parallel to the horizontal surface?

Describe the movement of tectonic plates in a mid-ocean ridge

Justify why does a bird flap its wing to fly higher?

A fax machine uses 0.106 A of current in its normal mode of operation, but only 0.040 A in standby mode. The machine uses a potential difference of 120 V.

What determines the mass of an object

Refer back to your data. List all indicators of chemical change that you observed.

Which of Newton's laws, when combined algebraically with his law of universal gravitation, can be used to calculate Earth's mass? A) first B) second C) third

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.