How do we usually hear things? Sound waves are made of ___ that pushes together ___.

A. energy, air particles

B. electromagnetic waves, parts of our ear

1. Strzała o masie 20 g tuż po wystrzale ma prędkość 50 m/s. Oblicz pracę wykonaną przez zawodniczkę. Ile wynosi energia potencjalna sprężystości napiętej cięciwy? 2. Na trampolinę o współczynniku sprężystości k=2 kN/m stanął zawodnik o masie 80 kg.

For a constant force, the impulse could be increased by: A. decreasing the distance. B. keeping the time the force acts constant. C. increasing the time the force acts. D. none of the other answers.

Who developed the heliocentric model

A piston uses 32 J of energy to do work as 68 J of heat are added to the cylinder of the piston. The change in internal energy of the system is ___ J.

A cell's functions include obtaining food and water and getting rid of ___. Is it bacteria?

Fourteen billion years represents the approximate age of?

An engineer uses aluminum to build an airplane rather than composite materials that are lighter and stronger. He does this because he is concerned about the composite materials and how suddenly they can fail. This is an example of:

Teresa wanted to test the effects of liquid density on the speed of sound waves. what is the dependent variable in her experiment?

A proton (mass = 1.67*10-27 kg, charge = 1.6*10-19 C) travelling with speed 1*106 m/s enters a region of space containing a uniform magnetic field of 1.2 T. What is the time t required for the proton to re-emerge into the field-free region? t =

A scientific_ is a rule used to discribe a pattern seen in nature not an examplanation of why that patten might occur