A 10 kg truck slides down a slide. It begins 12 m above the ground from rest and experiences no friction. Use the principle of conservation of mechanical energy,
a. to calculate its speed when he is at point B.
b. To calculate height at point C if its velocity is 5 m/s.

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )