Work
Work is equal to what?
Fnet * displacement
This is the definition of Kinetic Energy
What is the energy of motion?
The equation for Power involving work
What is P = work/time
Gravitational Potential energy is calculated by using the formula
What is GPE = mgh
W = F * d and Change in Kinetic Energy
What is the work energy theorem?
W = Change in Kinetic Energy
Rudolph has a mass of 300 kg and can fly at 5 m/s Donner has a mass of 200 kg and can fly at 6 m/s. Which reindeer has more kinetic energy?
Who is Rudolph?
Gravitational Potential Energy increases as this happens to an object
What is increasing the height of the object?
How do you find the change in kinetic energy?
Final - Initial Kinetic Energy
If you carry a 50kg box 15m along a level horizontal surface, how much work have you done?
What is zero?
Power is defined as
the rate at which work is done
In elastic potential energy, what does the k represent?
What is the spring constant (or how much force is required to stretch or compress it 1 m)?
A boy is pulling a wagon along the sidewalk. It has a kinetic energy of 17.7 Joules. The boy then applies a forward force of 26.6 Newtons for 3.52 meters. What is the new kinetic energy of the wagon?
111 Joules
If a 2kg box at rest is 5m high and set into motion going 10m/s at the bottom of the ledge, how much work did gravity do on the box?
What is 100J (or 98J is g=9.8)?
True or False Kinetic Energy can be negative
What is False?
How much power is required to take a 1500kg car from 10m/s to 20m/s in 10s?
What is 22500 Watts
[1/2(1500)(202)-1/2(1500)(102)]/10
True or False: An arrow is shot down from a rooftop at a velocity of v, a second one is shot from the same rooftop upward at a velocity of v, a third is shot purely horizontally at a velocity of v on the same rooftop. Which arrow has more kinetic energy when it reaches the ground?
Glynda glides to a stop across the icy pond from an initial speed of 6.90 m/s. Glynda weighs 557 Newtons and the coefficient of friction between her skates and the ice is 0.160. How far does she glide before she comes to a stop?
Remember friction = coefficient of friction * Fnormal (often equal to Fg)
15 m
A lift machine raises a 506 Newton box from the ground to a height of 19.8 meters in 15.6 seconds. What is power required of the motor to do this task?
642 Watts
A 2 kg ball is thrown horizontally at 4 m/s off a 10 meter cliff. It has this much Kinetic Energy when it hits the ground
What is 212 J
During peak shopping season at Northbrook Court, an escalator elevates 851 passengers a vertical distance of 8.70 meters over the course of 21.2 minutes. If the average mass of the passengers are 51.3 kg, determine the power required by the motor.
2926 Watts
A jolly 125 kg person holding a sack that weighs 25 kg stands on a rooftop that is 15 meters tall. The potential energy of this person and sack is...
What is 22,500 J
Claire deAisles exerts a 12.3-Newton rightward force upon an 97.6-Newton grocery cart to move it 2.95 meters down the frozen food aisle at Hy-Vee. If resistance forces are neglected, what would be the final speed of the cart?
Final speed: 2.7 m/s