Suppose an car engine could be made to burn at a higher ...

[Caiter2013]

Suppose an car engine could be made to burn at a higher temperature, without harming or altering any other part of the engine's operation. At the higher temperature, the engine would
 
  A) have a lower efficiency.
  B) have the same efficiency but be able to operate at a higher power.
  C) have a higher efficiency.
  D) still consume the same amount of gasoline per kilometer traveled.
  E) consume more gasoline per kilometer traveled.

Question 2

A 1.5-kg mass attached to an ideal massless spring with a spring constant of 20.0 N/m oscillates on a horizontal, frictionless track. At time t = 0.00 s, the mass is released from rest at x = 10.0 cm. (That is, the spring is stretched by 10.0 cm)
 
  (a) Find the frequency of the oscillations.
  (b) Determine the maximum speed of the mass. At what point in the motion does the maximum speed occur?
  (c) What is the maximum acceleration of the mass? At what point in the motion does the maximum acceleration occur?
  (d) Determine the total energy of the oscillating system.
  (e) Express the displacement x as a function of time t.

[Animal_Goddess]

Answer to Question 1

C

Answer to Question 2

(a) 0.58 Hz
(b) 0.37 m/s, at the equilibrium position
(c) 1.3 m/s2, at maximum displacement
(d) 0.10 J
(e) x = (0.10 m) cos(3.7t)

[Caiter2013]

Gracias!

[miss_1456@hotmail.com]

Wow, this really help