PS Unit 3 - Energy
10 J
A 5 kg medicine ball is thrown upward at a speed of 2 m/s. How much energy does it have?
150 J
A box weighing 30 N is pushed a distance of 5 meters. How much work was done? Be sure to include units.
8 J
A constant force of 2.0 N is used to push a box 4.0 m across the floor. How much work is done?
Electromagnetic energy
A form of energy that is reflected or emitted from objects in the form of waves that can travel through space.
insulator
A material that resists/limits the flow of heat by conduction, convection, and radiation is a(n) ____.
gravitational potential
The ____ energy of an object depends on both the height and the mass of an object.
They convert electrical energy to thermal energy.
What energy change do a blow dryer, iron, and toaster all have in common?
73.5 J
What is the potential energy of a 5 kg apple that is sitting on a 1.5 m high tree branch? Round your answer to the nearest tenth and be sure to include units
4,312 J
What is the potential energy of a 55 kg box that is sitting 8.0 m above the ground?
36 J
What is the potential energy of a puppy that weighs 18 N sitting in a high chair 2 m high? Be sure to include units.
Some of the ball's energy is converted to other forms, such as thermal and sound.
When a ball is dropped it bounces until it eventually stops. Why does this happen?
GPE goes down, KE goes up
When an object is dropped what happens to potential and kinetic energy as it falls?
potential energy
Which of the following types of energy does not directly result when a rocket is set off using chemical energy?
direct particle contact
Conduction is the transfer of heat energy by______
Kinetic energy
Energy in the form of motion.
gravitational potential energy
Energy stored by objects that are above the Earth's surface.
chemical potential
Energy stored in food would be considered
chemical potential energy
Green plants convert light energy from the sun into ____ during photosynthesis.
10 N
How much force is required to lift a rock a vertical distance of 8 m if 80 J of work were done?
4 W
How much power is used if a machine does 28 J of work in 7 seconds?
Conductor
Material that allows heat to flow easily.
Insulator
Styrofoam is an example of this.
kinetic energy
Temperature measures the average ____ of the particles in a material.
gravitational potential
The ____ energy of an object increases with its height.
speed
The kinetic energy of an object increases as its ___________ increases.
conservation of energy
The law of ____ states that energy in a system can change forms but can never be created or destroyed.
remains constant
The mechanical energy of a coconut falling from a tree ____.
power
The rate at which work is done is ____.
Radiation
Thermal energy is transferred to a solar panel by ____.
thermal energy
Transfer of energy by the movement of heated particles.
Work
Transfer of energy that occurs when a force makes an object move.
specific heat
Amount of heat needed to raise the temperature of 1 kg of a material by 1 degree Celcius.
sliding friction
An example of an energy conversion from kinetic to thermal energy would be
810 J
An object has a velocity of 9 m/s and a mass of 20 kg. What is the kinetic energy of the object?
in motion
An object that has kinetic energy must be
Mechanical energy
the total amount of kinetic and potential energy that an object has; energy associated with the motion and position of an object
