A solid uniform disk is rolling without slipping along a ...

[newyorker26]

A solid uniform disk is rolling without slipping along a horizontal surface with a speed of 4.5 m/s when it starts up a ramp that makes an angle of 25 with the horizontal.
 
  What is the speed of the disk after it has rolled 3.0 m up as measured along the surface of the ramp?
  A) 4.0 m/s
  B) 1.9 m/s
  C) 2.1 m/s
  D) 6.8 m/s
  E) 8.0 m/s

Question 2

Human reaction time is usually greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fall before you catch it, assuming negligible air resistance?
 
  A) at least 3.0 cm
  B) at least 4.9 cm
  C) at least 6.8 cm
  D) at least 9.8 cm

[jointhecircus]

Answer to Question 1

B

Answer to Question 2

B

[newyorker26]

TYSM

[flexer1n1]

Gracias!