1. An inclined plane is used to lift a box into a moving truck. The ramp is 6m long and 1.5m from the ground. What is the mechanical advantage of the inclined plane? 2. What is the mechanical advantage of the following pulley? The pulley has six supporting ropes but the force end is down.

3. The work output of a lever used to lift books is 30 Joules and the work input is 60 Joules. What is the efficiency of this lever?

4. Scott needs to split a chunk of wood for the fire. There is a crack in the chunk. If he uses an axe it will use 200 Joules of energy. He receives 100 Joules of work out of the machine.
A) What type of simple machine has he used?
B) What is the efficiency of the machine?

5 . Would you do more work moving 100 boxes weighing 12N for 1m or moving a 1000N box, 30cm? Support your answer.

the bal will not change its velocity.

chemical energy --> gravitational potential energy --> kinetic energy --> elastic potential energy --> gravitational potential energy

explanation:

when emma starts the hike, the chemical energy stored in her body is used to climb up the mountain, and so she gains gravitational potential energy (because at the end, she will be at a higher height h above the ground). then she goes bungee jumping: as she falls, this gravitational potential energy is converted into kinetic energy (because her speed increases as she falls down), until the point when the rope stretches, and she stops moving. at that moment, all the kinetic energy is converted into elastic potential energy due to the stretching of the rope. then, this energy is released because the rope returns to its natural length, and emma gains a small increase in altitude , so she gains some gravitational potential energy.