4. a cow has eaten 1500 kj of stored chemical energy in the form of food. 945 kj
is excreted as waste products. 495 kj is 'used for respiration.
a. how much of the original 1500 kj is stored as chemical energy in the
tissues of the cow? (1)
w b. the answer to part a is all the energy that can be transferred to a human.
calculate the efficiency of the energy transfer to the human. (hint: how
much of the original 1500 kj is transferred to the (3)

1. explain how you calculate the net force in any direction on the box. 2. suppose an upward force of 15n is added to the box. what will be the net vertical force on the box? 3. what force could be applied to the box to make the net force in the horizontal direction zero? explain. 4. suppose a force of 25n to the right is added to the box. what will be the net force to the right?

While strolling downtown on a saturday afternoon, you stumble across an old car show. as you are walking along an alley toward a main street, you glimpse a particularly stylish alpha romeo pass by. tall buildings on either side of the alley obscure your view, so you see the car only as it passes between the buildings. thinking back to your physics class, you realize that you can calculate the car's acceleration. you estimate the width of the alleyway between the two buildings to be 6 m. the car was in view for 0.6 s. you also heard the engine rev when the car started from a red light, so you know the alpha romeo started from rest 4 s before you first saw it. find the magnitude of its acceleration.

10. the kinetic theory of matter states that atomic particles will move if the temperature is above the freezing temperature of water atomic particles bounce off each other one time in their life atomic particles are constantly bumping off each other because particles are in direct contact with each other at all times all matter is made up of atomic particles which are in constant random motion