In physics, work is defined as
If you lift two loads up one story, how much work do you do compared to lifting just one load up one story?
If Nellie Newton pushes an object with twice the force for twice the distance, she does
The unit of work is the
Power is defined as the
The unit of power is the
Potential energy is the energy an object has because of its
Kinetic energy of an object is equal to
An arrow in a bow has 80 J of potential energy. Assuming no loss of energy to heat, how much kinetic energy will it have after it has been shot?
Energy is changed from one form to another with no net loss or gain.
As a pendulum swings back and forth
When a car’s speed triples, its kinetic energy
Rockets are launched from an airplane in the forward direction of motion. The kinetic energy of the airplane will be
A woman can lift barrels a vertical distance of 1meter or can roll them up a 2-meter long ramp to the same elevation. If she uses the ramp, the applied force required is
A job is done slowly, and an identical job is done quickly. Both jobs require the same amount of work but different amounts of
An object that has kinetic energy must be
Which requires more work: lifting a 40-kg sack vertically 5 meters or lifting a 20-kg sack vertically 10 meters?
Which has greater kinetic energy, a car traveling at 35 km/h or a half-as-massive car traveling at 70 km/h?
An object at rest may have
A heavy object and a light object are released from rest at the same height and time in a vacuum. As they fall, they have equal
Mechanical energy can be in the form of
Your car runs out of gas and you get out and push it. If you apply a force of 1030 N for 327 m (the distance to the nearest gas station), how much work did you do to push it?
What amount of work can a 600.-W do in 3.00 minutes?
A 25.0-kg girl climbs up a tree branch 3.0 m higher in 6.00 seconds. What is her power output?
The 2.0-kg head of an ax is moving at 3.0 m/s when it strikes a log and penetrates 0.030 m into the log. What is the average force the blade exerts on the log?
Casey and Ryan, pretending that they are playing in the jungle, suspend a rope from an overhead tree limb. Casey, of mass, 39.6 kg, runs horizontally at 8.09 m/s along the flat ground, grabs the rope, and swings off the level ground.
(a) How high does Casey get above the ground in his swing?
Casey and Ryan, pretending that they are playing in the jungle, suspend a rope from an overhead tree limb. Casey, of mass, 39.6 kg, runs horizontally at 8.09 m/s along the flat ground, grabs the rope, and swings off the level ground.
(b) Ryan, who is 26.6 kg, gives it a try and reaches a height of 3.13 meters above the ground? How fast was Ryan running to achieve this height?
EXTRA CREDIT: The coyote, whose mass is 24.62 kg, is chasing the roadrunner when the coyote accidentally runs off the edge of a cliff and plummets to the ground 89.7 m below. What force does the ground exert on the coyote as he makes a coyote-shaped dent 0.695 m deep in the ground?
A 37.06 kg hammer of a pile driver is lifted 16.8 m .
a) Find the potential energy of the driver at its maximum height.
A 37.06 kg hammer of a pile driver is lifted 16.8 m .
b) Calculate the velocity of the driver as it hits the ground when dropped from 16.8 m using the Work-Energy Theorem.
EXTRA CREDIT: A child is on a swing. Her mom pushes her to a height of 2.21 m above the starting position. Determine the child's maximum velocity during the swing.
