WorkMathPowerMachinesMisc

Question What is the SI unit for work?

Answer 1 – 10 Joule

Question What is the formula for work?

Answer 1 – 20 W = F x d

Question What is work?

Answer 1 – 30 The force acting upon an object to cause displacement

Question How much work is done if an object does not move?

Answer 1 – 40 None

Question How do these measurements compare: 5 J 5 N/m

Answer 1 – 50 Same

Question Calculate the machanical advantage of a wheel and axle where the wheel has a radius of 10 and the axle has a radius of 2

Answer 2 – 10 5

Question Two people lift two boxes having the same weight. Person 1 lifts his box in 6 seconds while Person 2 lifts his box in 3 seconds. Compare the power being exerted by these two people in this situation.

Answer 2 – 20 Person 2 uses twice or double the power.

Question The formula for power is P = work/time. If a weight lifter does 650 joules of work in 3 seconds pressing the bar over his head, how much power does he use?

Answer 2 – W

Question How much work is done while you raise a 50 Newton rock 5 m above the floor?

Answer 2 – J

Question A person pushes on a wall with 700 newtons of force for a minute. During this exertion the wall does not move. Describe the amount of work being done on the wall.

Answer 2 – 50 NONE

Question What is the SI unit for Power?

Answer 3 – 10 Watt

Question An increase in power means there was a … – Increase in time – Decrease in work – Increase in distance – Increase in work

Answer 3 – 20 Increase in work

Question Identify the formula to find Power.

Answer 3 – 30 P = W/t

Question What is power?

Answer 3 – 40 The rate at which work is done.

Question How do you increase power output?

Answer 3 – 50 Work faster / complete it in less time.

Question What type of simple machine does a pencil sharpener contain?

Answer 4 – 10 Wheel and axle

Question Which of the following can machines such as levers and pulleys do? – Change directions of forces – Multiply forces – Be used to gain mechanical advantage in work output – All of the above

Answer 4 – 20 All of the above

Question What type of simple machine would NOT increase force?

Answer 4 – 30 A fixed pulley

Question Simple machines transfer what?

Answer 4 – 40 Force

Question Which of the three things listed below can machines do? – Increase force applied to an object – Increase distance over which force is applied – Change the direction of a force – All of the above

Answer 4 – 50 All of the above

Question Name a 1 st class lever example

Answer 5 – 10 Seesaw Crowbar/prybar

Question The equation MA = output force / input force is for which type of mechanical advantage?

Answer 5 – 20 AMA

Question MA = input distance / output distance is which type of mechanical advantage?

Answer 5 – 30 IMA

Question Work is described as: – The ability to transfer heat – The ability to convert energy – The force applied that gives an object weight – The force applied to an object times the distance the object moves

Answer 5 – 40 The force applied to an object times the distance the object moves

Question What is the mechanical advantage of the following pulley

Answer 5 – 50 MA = 4