- How do we use friction in our everyday lives?

- Name 3 professionals that have to consider friction when doing their job. Explain

Warm up

Rubber meets the Road• Finish your Questions from yesterday and

then answer the following questions in your journal:

Kinetic Energy

• http://www.brainpop.com/science/energy/kineticenergy/

• Get a whiteboard and Marker!!• What unit would I use for the following:

– Work– Kinetic Energy– Power– GPE– Force

- 2 hikers climbed a 1200 meter mountain. Hiker #1 is 43 kg and climbed the mountain in 3 hours the other hiker #2 is 72 kg climbed the mountain in 5 hours. How much power did each hiker have?

On your Whiteboard

• If a force is being applied on an object how do you know if the thing applying force is doing work to the object?

• A 56 g bird flies at an acceleration of 4m/s2 to escape a circling hawk. How much Force does this bird have?

• A 7345 g dog runs to it’s owner with a force of 4.5 N. What is the acceleration of the dog?

• How much force would the owner need to stop the dog?

• How much power would a 2 ton car have that pulled a camper 400cm with a force of 20 N in 10 seconds.

• When you step into clay and make a foot print are you transferring any energy?

• Are you transforming any energy? If so explain?

• Draw an energy chain of a tennis player hitting a ball. Start will the racket pulled back ready to swing and the ball in motion in front of the player end with the ball hitting the ground

• If I told you that within a closed system a system only has 3 forms of energy KE, GPE, and HE and this system had the following:– 1542 J of total energy – 134 J of Kinetic Energy – 1045 J of GPE How much HE would the system have? What law would help explain this?

• What is the kinetic energy of a .46 kg bullet traveling 500 m/s?

• What is the kinetic energy of a .53 kg bullet traveling 200 m/s?

• Calculate the kinetic energy in joules of a 4000 kg car moving at the following speeds:

 • 47.52 m/s

• 22 m/s

• Calculate the GPE in the following systems: 

• a car with a mass of 1890kg at the top of a 52m high hill

• a 74 kg climber on top of Mount Everest (8900 m high)