Energy 1
What type of energy transformation occurs when you turn on a light bulb?
Electrical energy → Light energy (and some heat energy (Thermal)).
A push or pull is an example of a
Force
The type of potential energy found in food, gas, or batteries
Chemical energy
Visible light also called Radiant energy is a part of _____________________ energy.
Electromagnetic
The rate at which work is done is called?
Power
Explain the energy changes that occur when you strike a match.
Mechanical energy → Chemical energy - Heat energy (Thermal) → Light energy (Electromagnetic/Radiant).
An objects change in position relative to a reference point.
motion
A hair dryer converts electric energy into-
thermal energy, mechanical energy, and sound energy.
How does energy transformation occur in the photosynthesis process within plants?
Light energy (from the Sun) → Chemical energy (stored in glucose).
The formula and unit for power.
Power = Work / time. We call this Watts (W)
In a roller coaster, identify the points where potential and kinetic energy dominate and describe the transformations during the ride.
At the top: mostly potential energy. As it descends: potential energy changing to kinetic energy. At the bottom: mostly kinetic energy.
Force is measured in this unit called a ________.
Newtons
Elastic and Gravitational are both types of this type of energy
Potential energy
Complete this sentence.
Work is done when a force acts on an object in the ____________ the object _________.
"Work is done when a force acts on an object in the direction the object moves."?
Nuclear, and Chemical energy are types of ______________ energy.
Potential
What energy transformations happen in a wind turbine used to produce electricity?
Kinetic energy (moving air) → Mechanical energy (turbine rotation) → Electrical energy.
What is the formula to calculate work?
Work = Force x Distance
When a ball is thrown straight up, how does its energy change from the moment it leaves your hand to when it hits the ground?
Kinetic energy (throw) → Potential energy (as it rises) → Kinetic energy (as it falls)
What is the gravitational energy of a cat that weighs 40 newtons lifted 2 meters above the ground?
Gravitational potential energy = weight x height above ground. 80J
To increase power, you can ___________ (increase/decrease) the amount of work done in a given time, or you can do a given amount of work in__________(more/less) time.
"To increase power, you can increases the amount of work done in a given time, or you can do a given amount of work in less time."?
When a car engine runs, what are the major energy transformations that take place?
Chemical energy (in fuel) → Heat energy → Mechanical (kinetic) energy → Sound energy.
How force and motion relate to work.
For work to occur, the force on an object has to be in the same direction as its motion.
Potential Energy plus Kinetic Energy is called?
Mechanical Energy
Provide the formula for work. Then use the formula to answer the following question:
How much work was done? Sally moved her couch 5 m with a force of 15 newtons.
What is work = force x distance?
What is 75 joules?
A girl with a mass of 50kg is jogging at a speed of 2 meters per second. What is her kinetic energy?
1/2 x 50 x 22
= 100J