Grade 8 Chapter 2 Quiz

The Law of Conservation of Energy states that

• energy cannot be transformed from one area to another

• energy can be transformed from one form to another, but it cannot be created or destroyed

• energy can be created or destroyed when it changes form

• energy stays in the same form and moves from place to place

Which is NOT an example of work?

• pushing a shopping trolley through the shop

• lifting a box from the table and putting it on the shelf

• throwing a ball

• holding a box in your arms

If Mayram lifts a box with a weight of 10N over a distance of 10 m, how much work is she doing on the box?

• 1 J

• 10 J

• 100 J

• 100 N

Which of the following is gravitational potential energy?

• the energy stored in an object that is 10m above the ground

• the energy of an electron moving through a wire

• the energy stored in the bonds of a carbohydrate molecule

• the energy stored in an uranium atom

which form of energy is NOT carried by waves

• chemical

• radiant

• seismic

• sound

How can a simple machine make work easier?

• by increasing the amount of work done

• by decreasing the amount of work done

• by changing the distance or the force needed to do work

• by getting rid of the work needed to move an object

What does all energy have?

• size and shape

• mass and volume

• the ability to cause change

• the ability to transport matter

A ring-pull on top of a can is an example of

• an inclined plane

• a lever

• a pulley

• a wedge

A screw makes work easier because it

• makes work over a longer distance

• decreases the force you need to input

• changes the direction of the force that acts in a straight line to one which rotates

• pivots around a central point

A bicycle is a complex machine because

• it is made up of one large machine

• it is made up of several simple machines working together

• it changes kinetic energy to thermal energy

• it is efficient