The correct answer is 19.72 °C. The first step is to determine the amount of heat that was lost per gram (30,000 J) / (390 g) = 76.92 J/g. Then to determine the temperature change, divide 76.92 J/g with the given specific heat of milk (76.92 J/g) / (3.9 J/g°C) = 19.72 °C.
The wall exerts a force of equal magnitude but in the opposite direction. So the force by the wall is 10 N to the right.
The forces that make a passenger speed up, slow down, or
turn a curve are the same forces that have the same effect
on the driver and anybody else in the car.
-- Speeding up . . .
the back of the seat
friction between the car seat and the seat of your pants
-- Slowing down . . .
the seat belt
friction between the car seat and the seat of your pants
-- Turning away from a straight line . . .
the seat belt
friction between the car seat and the seat of your pants
the door, or whatever or whomever you're leaning against
To solve this problem we will apply the principles of energy conservation. On the one hand we have that the work done by the non-conservative force is equivalent to -30J while the work done by the conservative force is 50J.
This leads to the direct conclusion that the resulting energy is 20J.
The conservative force is linked to the movement caused by the sum of the two energies, therefore there is an increase in kinetic energy. The decrease in the mechanical energy of the system is directly due to the loss given by the non-conservative force, therefore there is a decrease in mechanical energy.
Therefore the correct answer is A. Kintetic energy increases and mechanical energy decreases.
kinetic energy is Movement energy
think of it like the Xbox Kinect
