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Flashcards in Power Deck (20)
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1
Q

What is power about?

A

Rate of energy transferred.

2
Q

Power is the rate…

A

Of doing work.

How much per second.

3
Q

What is power not the same as?

A

Force.

Energy.

4
Q

What is a powerful machine?

A

It transfers a lot of energy in a short space of time.

5
Q

What is the formula for power?

A

Work done(or energy transferred)
Divided by.
Time taken.

6
Q

E
_ EQUALS

T

A

P - Power.

7
Q

What is power measured in?

A

Watts.

j/s.

8
Q

What does one watt equal too?

A

1 joule of energy transferred per second.

9
Q

What does power mean?

A

How much energy per second.

10
Q

Kj has to be turned into…

A

j.

11
Q

Minutes has to be turned into…

A

Seconds.

12
Q

Name 2 ways to measure the power output of a person?

A

The Timed Run Upstairs.

The Timed Acceleration.

13
Q

What happens in The Timed Run Upstairs?

A

Energy transferred is the potential energy you gain.

14
Q

How do you get the power output from The Timed Run Upstairs?

A

Mgh/t.

Mass x acceleration due to gravity x height divided by time taken.

15
Q

What does mgh/t mean?

A

M - Mass of the object.
G - Acceleration due to gravity = 10
H - Height of the object.
T - Time taken.

16
Q

What does mgh/t equal?

A

W - Power.

17
Q

What happens in The Timed Acceleration?

A

Energy transferred is kinetic energy you gain.

18
Q

How do you get the power output from The Timed Acceleration?

A

1/2mv2/t

1/2 x mass x velocity2 divided by time taken.

19
Q

What does 1/2mv2/t mean?

A

1/2
M - Mass of the object.
V2 - Velocity squared.
T - Time taken.

20
Q

How do you get accurate results from the experiments?

A

Repeat several times.