Work
The equation for work given a Force and a Distance.
What is W = F * d
or
W = F * d * cos 0?
The equation for Kinetic Energy.
What is KE = 1/2 * m * v^2 ?
The equation for gravitational potential energy.
What is PE_g = m * g * h ?
What is P = W / t
or
P = F * v?
The equation for momentum.
What is p = m * v?
What is the force on an object that moved 16m with 88 J of work done on it?
The force on the object is 5.5 N.
What is the kinetic energy of a 60 kg person running at 8 m/s?
The kinetic energy of the person will be 1920 J.
What is the gravitational potential energy of a 25kg child about to dive off a 15m high diving board?
The gravitational potential energy of the child is 3679 J.
When 60 joules of work are done in 5.0 seconds, what is the power developed?
The power developed is 12 W.
What is the momentum of a 1750 Kg car driving at 25 m/s?
The momentum of the car is 4.38 x 104 kg*m/s
or 4.38 x 104 N*s.
How much work is done pushing a car with a force of 8000N for 25m up a hill with an incline of 25 degrees?
(Answer in Scientific Notation)
The work done is 2 x 105 J.
A car has a kinetic energy of 2x105 J when traveling at a speed of 15 m/s. What is the mass of the car?
The mass of the car is 1778 kg.
What is the gravity on a planet where a 15 kg object has 150 J of potential energy when 30 m above the ground?
The gravity on this planet is .3 m / s2
A force of 40 newtons must be exerted to keep a car moving with a constant speed of 5 meters per second. What is the rate at which energy must be supplied?
The power rating is 200 W.
What is the speed and direction of a 3500 kg plane traveling with a momentum of 1.5 x 105 N-s due South?
The speed and direction of the plane will be 42.9 m/s South.
A tugboat pulls a ship with a constant net horizontal force of 9 x 103 N. How much work is done on the ship if it moves 3 km? (Answer in Scientific Notation)
The work done by the tugboat on the ship is 2.7 x 107 J.
What is the speed of a 1500 kg car with kinetic energy 3.2 x 10^3 J?
The speed will be 2.06 m/s
A person weighing 600 newtons rides an elevator upward at an average speed of 3 meters per second for 7 seconds. How much does the person's gravitational potential energy increase as a result of this ride?
The gravitational potential energy will increase by 12600 J.
How long will it take a 20kW steam engine to perform 4 x 105 J of work?
Two roller skaters, one weighing 30 kilograms and one weighing 50 kilograms, are initially at rest. The 50 kilogram roller skater exerts a force of 30 newtons on the 30 kilogram roller skater for 0.5 seconds. What is the magnitude of the impulse applied to the 30 kilogram roller skater?
The impulse will be 20 kg * m / s (or 20 N * s).
What is the average acceleration on a 5kg object that had 1350J of work done on it over 120m?
The average acceleration of the object is 2.25 m/s2
What final speed will an acorn have after it drops from a limb 10 m high?
The final speed will be 14 m/s.
A skydiver with a mass of 40kg drops out of a plane flying at 1200m following a path with an angle 30 degrees below the horizontal. What is his gravitational potential energy when he is 500m from the drop point?
(Answer in Scientific Notation)
His gravitational potential energy is 3.73 x 105 J.
A rain cloud contains 3 x 106 kg of water vapor. How long would it take a 5 kW pump to raise that same amount of water to an altitude of 1 km.
(Scientific Notation Answer)
It would take 5.89 x 106 s.
Which of the following situations has the least momentum?
A mouse running from a cat
A person walking down the sidewalk
A car driving home from work
A train in the station
A train in the station will have 0 velocity, and therefore the lowest momentum.