A ball is thrown upward at a velocity of 19.6 m/s. What is its ...

[bio_gurl]

A ball is thrown upward at a velocity of 19.6 m/s. What is its velocity after 3.0 s, assuming no air?
 
  A) 9.8 m/s upward
  B) 9.8 m/s downward
  C) 0 m/s
  D) 19.6 m/s downward

Question 2

Dust particles are pulverized rock, which has density 2500 kg/m3. They are approximately spheres 20 m in diameter.
 
  Treating dust as an ideal gas, what is the root-mean-square speed (thermal speed) of a dust particle at 400C? (The Boltzmann constant is 1.38  10-23 J/K.) A) 5.2  10-5 m/s
  B) 1.7  10-5 m/s
  C) 3.0  10-5 m/s
  D) 7.3  10-5 m/s

[lcapri7]

Answer to Question 1

B

Answer to Question 2

A

[bio_gurl]

Gracias!

[at]

Thanks for the timely response, appreciate it