Energy 2 Flashcards
The energy required to make a car move along a flat road, to launch a rocket into outer space and to
operate a small calculator is transformed from
Chemical energy
The faster an object moves
More kinetic energy it has
A group of sheep are grazing in a field. As they eat, the sheep break down the molecules in the
grass, which releases energy. Which form of energy is stored in the grass?
Chemical potential energy
Four different brands of batteries each stores 5.5 kJ of energy. The table below shows how much
electrical energy each battery releases.
Brand A B C D
Electrical energy released (kJ) 4.25 4.32 4.19 4.07
Brand B
A particular electric knife is 40% efficient. If 100 J of energy is supplied to the knife, the number of
joules that is then transformed into kinetic energy is
40
When a hand held fan turns, the blades spin. Which diagram shows the energy conversion to make the
fan work?
Chemical electrical kinetic
Heated air rises, cools, and then sinks. Air near a heater is
replaced by cooler air, and the cycle repeats. This is an example of
Convection
An object in which thermal energy moves easily is called
A conductor
The transfer of heat by the passing of vibrations from particle to particle in a substance is called
Conduction
The law of reflection states that the angle of incidence equals
The angle of reflection
Which statement about light is false?
A. If light did not travel in straight lines there would be no shadows. B. Light can be made to travel around corners using mirrors. C. You can only see this page because light reflects off the page into your eyes. D. No letter of the alphabet looks the same when viewed in a mirror.
D
A metal pole attached to a net used to clean a pool looks bent when it is standing up inside a pool. The
process that explains why this happens is called
Refraction
. The figure below shows the path of a ray of light when travelling from air to glass. Which is the angle
of incidence?
Angle A
What happens to the speed of light when it travels into glass or Perspex from the air?
It slows down
The action of the lens in obtaining a sharp image on the retina is called
Accommodation
What is the function of the optic nerve in the eye?
A. It sends electrical messages to your brain.
In a normal human eye, the image is formed
On the retina
In the eye disorder known as long-sightedness, the image of an object forms behind the retina. Long-
sightedness is corrected by bringing the image forward using
convex lenses that bend the light more.
A ray of light passes through a window. Which path
does it take?
C
A parallel beam of light falls on a converging lens.
Which diagram shows what happens to the beam of light?
D
chemical energy into kinetic energy
Car
elastic potential energy into kinetic energy.
Catapult
When particles very close together, such as in a solid, vibrate the
heat is moved from particle to particle.
Conduction
Heat causes the particles to gain energy and spread apart, as in a liquid.
Convection
