Simple machines

What is a machine?

• A device that requires electricity to operate.

• A tool used only in construction.

• A device that helps us do work more easily by moving an object over a distance.

• A computer program that performs complex calculations.

What is the equation that represents the amount of work done?

• Work = Distance / Force

• Work = Force x Distance

• Work = Force / Distance

• Work = Distance x Speed

What is the term for the force that you apply to a machine?

• Output force

• Distance force

• Input force

• Work force

Can simple tools like hammers and screws be considered machines?

• No, because they do not use electricity.

• Yes, because they change forces and make work easier.

• No, because they are not complex gadgets.

• Yes, because they can only be used in construction.

If a machine increases the distance over which the force is applied, what must it do to the force according to the text?

• The machine must increase the force.

• The machine must decrease the force.

• The machine must keep the force the same.

• The machine must apply the force over a shorter distance.

What is the relationship between force and distance when a machine makes work easier?

• Work equals force times distance, so increasing one decreases the other.

• Work equals force divided by distance, so increasing one increases the other.

• Work equals force plus distance, so increasing one has no effect on the other.

• Work equals force minus distance, so increasing one increases the other.

Which of the following is an example of a machine that increases force by increasing the distance over which the user applies the force?

• A hammer

• A steering wheel

• A screwdriver

• A pulley

How does a pair of pliers increase force?

• By moving the handles a shorter distance than the squeezing end.

• By moving the handles a greater distance than the squeezing end.

• By keeping the distance the handles and the squeezing end move the same.

• By reducing the distance both the handles and the squeezing end move.

What does using pliers allow you to do compared to using your fingers alone?

• Squeeze objects with less force

• Squeeze objects with more force

• Squeeze objects over a longer distance

• Squeeze objects with the same force as your fingers

What is the trade-off when using machines that increase the distance over which force is applied?

• The machine applies more force than is applied to it

• The machine applies the same amount of force as is applied to it

• The machine applies less force than is applied to it

• The machine does not apply any force