- #1

wisehemlock

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**please help me I need to get this done!**

I have a this big assignment to get in, in not a big portion of my grade but I'll still get 2 days detention if I don't get it in, and I have to go to an important meeting tomorrow. This teacher is noted as being one of the worst at my school, she's totally incompetent, and no one likes her teaching methodes. To put it simply I LOVE Science and usually have a 96% or higher, this is the ONLY semester I have NOT...tell me there isn't a connection..! anyway here are the questions I CAN'T answer, since I have to have it in by midnight can someone PLEASE help me, I'm losing my mind!

(1.) Calculate the Mass.

PE = 1250J

Height = 6m

velocity = 2m/s

Possible Answers:

208.3kg

21.3kg

73500kg

or

21.3 g

______________________________________…

(2.) KE = 3000J

velocity = 8 m/s

Possible Answers:

96000 kg

187.5 kg

46.9kg

93.8kg

______________________________________…

(3.) Calculate the kinetic energy if an object that has a mass of 6kg is moving 3m/s2.

Possible Answer:

9J

18J

27J

27kJ

________________________________________…

(4.) Using the f=ma and w=fd formulas, calculate work if:

mass = 20kg

acceleration = 3m/s2

distance = 40m

Possible Answers:

1.5 J

2400N

2400J

240 J

________________________________________…

(5.) _________ describes potential energy.

Possible Answers:

stored energy

m/s2

mass times acceleration due to gravity

energy in motion

________________________________________…

(6.) How much work was done during the 1000m of the race?

Given Information:

During a bicycle race, a cyclist who had a mass of 50kg used a bike with a mass of 20kg. As he began the race, he was able to displace 100m the first 10sec of the race. As the race continued, his velocity increased to 25m/s at exactly 20sec of the race. He was able to maintain this acceleration for a total of 1000m.

Possible Answers

1050kJ

70000J

75000J

1500J

1500N

105000J

________________________________________…

(7.) What is the mass of a golfball that has a momentum of 1 kg*m/s and is moving 25m/s?

0.04kg

100 kg

25 kg

0.04 kg*m/s

______________________________________…

(8.) ______________ describes kinetic energy.

Possible Answers:

energy in motion

stored energy

mass x acceleration due to gravity x height

Newton

________________________________________…

(9.) What unit describes work?

Possible Answers:

m/s2

N-m/s

J

kg *m2/s

________________________________________…

(10.) What is the total energy of a system that has 4000 J of potential energy and 1000 J of kinetic energy?

Possible Answer:

3000J

4 kJ

4000000 J

5000J

________________________________________…

(11.) Calculate power if it takes 60seconds to complete 30J of work.

Possible Answers:

2 W

0.5 W

1800 W

0.5 J

________________________________________…

(12.) Another way to describe a Newton is

Possible Answers:

kg*m*s

kg*m/s

m/s2

kg*m/s2

________________________________________…

(13.) Calculate distance if

work = 300J

and force = 3N

Possible Answers:

100m

10m

900m

10J

________________________________________…

(14.) What is the potential energy of a 0.5kg grapefruit just before it is dropped off a building rooftop that is 150m in height?

Possible Answers:

75 J

11250J

735 J

367.5 J

________________________________________…

(15.) What unit describes force?

Possible Answers:

Newton

joule

N-m

N-m2

________________________________________…

(16.) Calculate power if a it took a force of 30N to push a car a distance of 20m. The time it took to move the car 20 m was 0.5min.

Possible Answers:

20W

120 W

1200 W

1W

________________________________________…

(17.) Given Information:

During a bicycle race, a cyclist who had a mass of 50kg used a bike with a mass of 20kg. As he began the race, he was able to displace 100m the first 10sec of the race. As the race continued, his velocity increased to 25m/s at exactly 20sec of the race. He was able to maintain this acceleration for a total of 1000m.

If the cyclist hit a car at exactly 20secof the race, what force would he exert on the car?

Possible Answers:

105N

1250N

700N

75N

70kg

________________________________________…

(18.) What is the height of a tree if a 0.1kg apple has 20J of potential energy just before it falls to the ground?

Possible Answers:

20.4m

200m

40.8m

2.0m

________________________________________…

(19.) How long does it take to perform 100J of work with a power rating of 20W?

Possible Answers:

5 W

2000 W

5s

0.5 s

________________________________________…

(20.)What is the mass of an object that has 450J of kinetic energy and is moving at 30m/s?

Possible Answers:

15kg

1kg

30kg

0.5 kg

______________________________________…

(21.) Use the given information to calculate velocity:

mass = 60kg

PE = 3000 J

KE = 4000J

Possible Answers:

11.5m/s

89.4m/s

10m/s

133.3 m/s

______________________________________…

(22.) The final unit when calculating kinetic energy is _______.

Possible Answers:

Newton

kW

Joules

watt

________________________________________…

(23.) USe the given information to calculate potential energy:

mass = 50kg

velocity = 3m/s

height = 4m

Possible Answer:

1960J

5880J

600J

225J

________________________________________…

(24.) Calculate work if :

f= 30N and distance = 3000m

Possible Answers:

90000J

100J

9000J

90000N

______________________________________…

(25.) Calculate time if:

force = 25N

distance = 1000cm

power rating = 5W

Possible Answers:

5000s

500s

5 min

50s

Sorry There's so many, This isn't all of them F.Y.I. so I wasn't just like "hey man do this all for me." There's 57 questions, these are just the one's that I can't do. Please help me out! I have a spliting headache and I am EXTREMELY stressed out. Thank you!