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Question 1

energy

Answer 1

the something that enables an object to do workulc

Question 2

fulcrum

Answer 2

pivot point

Question 3

joule

Answer 3

unit of work when 1 n exerted over a distance over i meter work= force x distance

Question 5

potential

Answer 5

stored energy by virtue of its position

Question 6

law of conservation of energy

Answer 6

in the absence of an external force, the momentum of a system remains the same

Question 7

lever

Answer 7

a rigid bar with a pivot point

Question 8

machine

Answer 8

a device used to change the applied ofrce and/or the direction of that force

Question 9

mechanical advantage

Answer 9

ratio of output force to input force

Question 10

power

Answer 10

rate at which work is done

Question 11

pulley

Answer 11

a grooved wheel which cord is pulled through

Question 12

watt

Answer 12

unit of power

Question 13

work

Answer 13

energy transferred by force

Question 14

Formula for work? -

Answer 14

force x distance (w=fd)

Question 15

A person pulls a sled with the force of 20 N for a distance of 200 m, how much work was done?

Answer 15

4000 Nm

Question 16

Same action above was done in 80s, how much power?

Answer 16

50 watts

Question 17

Describe what happens to the amounts of PE and KE when you pick an object up and drop it.

Answer 17

Potential energy rises as you pick it up and kinetic energy stays the same. When you drop it the kinetic energy increases and the potential energy decreases. When it hits the ground the kinetic energy is back to zero.

Question 18

Explain how no energy is actually lost when a campfire is burning. The fuel (wood) is transferred to what other types of energy?

Answer 18

The fuel turns into light energy and heat energy—the ones that we can feel and see.
The energy just changes forms. The energy is transferred into heat energy

Question 19

A lever with the fulcrum moved closer to the load than the effort trades ___ for __.

Answer 19

distance; force

Question 20

Show the 3 classes of levers.

Answer 20

First: fulcrum between load and effort
Second:load between fulcrum and effort
Third: effort between fulcrum and load

Question 21

“I can’t lift 500 lbs one time but I can lift 10 lbs 50 times,” is talking about ________.

Answer 21

mechanical advantage