12. You carry a lost puppy that weighs 30 N up a flight of stairs 10 m high. a) Identify the energy transfer that occurred as you carried the puppy up the stairs.

Explanation:

The puppy starts and ground level and goes up a flight of stairs 10 m weighs 30N. The weight doesn't change so the only thing that can is the height.

Energy change = F * d

Energy change = 30 * 10

Energy change = 300 J

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.