Examples in daily life that air has mass

You have a ball in your hand above the ground at rest which you then drop. What energy is involved in each part of this situation and how do we know that total mechanical energy has been conserved? Explain with and without air resistance present.

A toy race car travels down a 25cm ramp in 5 seconds. Calculate its speed. A. 125 cm/sec B. 5 cm/sec C. 0.2 cm/sec D. 20 cm/sec

Which of these best explains why the hydrogen atoms in a water molecule are attracted to CI ions in sodium chloride

What happens when the thermal energy of a substance increases? A: The motion of the particles in the substance increases, and the temperature of the substance decreases.

What is the advantage of adding more pulleys to a system of pulleys?

Why does icing sugar dissolve more rapidly than granular sugar?

At t = 0 the components of a radio-controlled car's velocity are vx = 0.5 m/s and vy = 1.2 m/s. Find the components of the car's velocity at t = 4.

2) A window washer pulls themselves upward using a bucket pulley apparatus. A) How hard must pull downward to raise herself slowly at a constant speed? B) If she increases this force by 15%, what will her acceleration be?

A star with an original mass of 8 to 25 solar masses will ultimately become a? a) red giant b) white dwarf c) neutron star d) main sequence star

Racewalking involves more impact than running. true false