A 0.60-kg object is suspended from the ceiling at the end of a ...

[jeatrice]

A 0.60-kg object is suspended from the ceiling at the end of a 2.0-m string. When pulled to the side and released, it has a speed of 4.0 m/s at the lowest point of its path. What maximum angle does the string make with the vertical as the object swings up?
 a. 61
  b. 54
  c. 69
  d. 77
  e. 47

Question 2

Any change of the energy of a system occurs because of
 a. energy transfer across the boundaries of the system.
  b. combustion of fuels within the system.
  c. radioactive decay of elements within the system.
  d. all of the above. e. only (b) and (c) above.

[ASDFGJLO]

Answer to Question 1

B

Answer to Question 2

A