Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth...
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![Page 1: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/1.jpg)
Review for Energy Exam
![Page 2: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/2.jpg)
What is the work required for 60 kg astronaut to lift herself
0.2 m on Earth
0.2 m
Ans. 120 J
![Page 3: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/3.jpg)
What is the work required for a 60 kg astronaut to lift herself
0.2 m on Planet X? (g = 2 m/s2)
0.2 m
Ans. 24 J
![Page 4: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/4.jpg)
What is the PEg of a 20,000 kg lunar lander that is 100 m
above the surface of the Moon?
(g = 2 m/s2)
100 mAns. 4,000,000 J
![Page 5: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/5.jpg)
What is the KE at point C?
h
½ hPE = 0
PE KE
20 J
A
B
C
D
Ans. 10 J
![Page 6: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/6.jpg)
What is the speed of the 1 kg ball at point C?
h
½ hPE = 0
PE KE
20 J
A
B
C
D
Ans. 4.5 m/s
![Page 7: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/7.jpg)
The car at B has _____ times as much KE as it had at A
20 m/s 40 m/s 60 m/s
A B C
Ans. 4
![Page 8: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/8.jpg)
The car at C has _____ as much KE as it had at A
20 m/s 40 m/s 60 m/s
A B C
Ans. 9
![Page 9: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/9.jpg)
What is the primary form of energy present in this situation?
Ans. PEs
![Page 10: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/10.jpg)
What form(s) of energy are present in this
situation?
Ans. PEs, PEg
![Page 11: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/11.jpg)
What was the work done on the 1000 kg car?
5 m/s 25 m/s
Before After
Ans. 300,000 J
![Page 12: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/12.jpg)
A 5 kg lead ball and a 2 kg
wooden ball are dropped from
the same height. Which has more
PEg?Ans. Lead ball
![Page 13: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/13.jpg)
A 5 kg lead ball and a 2 kg
wooden ball are dropped from the
same height. How do their KEs compare before
striking the ground? Ignore air resistance.
Ans. Lead KE is greater
![Page 14: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/14.jpg)
A 5 kg lead ball and a 2 kg
wooden ball are dropped from the
same height. How do their
speeds compare before striking the ground? Ignore air resistance.
Ans. Speeds same
![Page 15: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/15.jpg)
The motion of a 2 kg cart is shown below. What is its KE
at t = 6 s?
0
30
60
0 1 2 3 4 5 6 7 8 9 10
11
12
13
14
15
16
17
18
19
20
Time (sec)
Velocity (m/s)
Ans. 900 J
![Page 16: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/16.jpg)
If Sally and Sam have the same mass, which one has the greater
KE?
00
position
time
SamSally
Ans. Sally
![Page 17: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/17.jpg)
What forms of energy does the baseball have?
Ans. KE, PEg
![Page 18: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/18.jpg)
What is the stiffness (k) of this spring?
0
30
60
0 1 2 3 4 5 6 7 8 9 10
11
12
13
14
15
16
17
18
19
20
Stretch (m)
Force (N)
Ans. 6 N/m
![Page 19: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/19.jpg)
What is the PEs when the spring is stretched to 5 m?
0
30
60
0 1 2 3 4 5 6 7 8 9 10
11
12
13
14
15
16
17
18
19
20
Stretch (m)
Force (N)
Ans. 75 J
![Page 20: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/20.jpg)
If all of the PEchem of a typical doughnut could
be used to do work, how high could a 50 kg
person climb?
PEchem = 1,000,000 J
?Ans. 2 km
![Page 21: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/21.jpg)
A skier has a choice of the following two frictionless slopes. Along which slope will he end up with the greatest
speed at the bottom?
Slope A Slope B
Ans. Same speed
![Page 22: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/22.jpg)
A diver falling from 2h will have _____ as much KE hitting the water as a diver
falling from h
Ans. twice
![Page 23: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/23.jpg)
A diver falling from 4h will have _____ as much speed hitting the water as a diver
falling from h
Ans. twice
![Page 24: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/24.jpg)
A 20 kg kid starts from rest at point A. What is his PEg at A?
6 m
3 m
A
B
C
Ans. 1200 J
![Page 25: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/25.jpg)
What is the 20 kg kid’s PEg at point C?
6 m
3 m
A
B
C
Ans. 600 J
![Page 26: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/26.jpg)
What is the 20 kg kid’s KE at point B?
6 m
3 m
A
B
C
Ans. 1200 J
![Page 27: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/27.jpg)
What is the 20 kg kid’s KE at point C?
6 m
3 m
A
B
C
Ans. 600 J
![Page 28: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/28.jpg)
What is the 20 kg kid’s speed at point B?
6 m
3 m
A
B
C
Ans. 11 m/s
![Page 29: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/29.jpg)
What is the work done on the dog? Into what form of energy
does this work go?
Dog slides 2 m
30 N
Dog is motionless at end
Ans. 60 J; thermal
![Page 30: Review for Energy Exam. What is the work required for 60 kg astronaut to lift herself 0.2 m on Earth 0.2 m Ans. 120 J.](https://reader035.fdocuments.net/reader035/viewer/2022062805/5697c0041a28abf838cc4796/html5/thumbnails/30.jpg)
After hitting a 0.4 kg soccer ball with her head, it travels 6 m straight up.
What was the work she did on
the ball?
6 m
Ans. 24 J