How Is Kinetic Energy Related to Cue Ball Motion in Pool?

AI Thread Summary
The discussion revolves around solving physics problems related to kinetic energy and motion. Participants are working through calculations for the work done on a cue ball, its resulting speed, and the distance from the Earth to the sun based on light travel time. There are also inquiries about calculating time for an electron's displacement and average velocity for a person's journey. Clarifications on using the correct equations and units are provided, emphasizing the importance of accurate calculations and understanding fundamental physics concepts.
say_uri
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Hello , i need some help solving a few questions. please help :) thankyou

a)A pool Cue exerted an average force of 160N on a cue ball over a distance of 0.012m How much work did the cue do on the ball.

b)If all the work done on (a) was transformed into kinetic energy of 0.0200kg cue ball, what was the speed of the ball?

c) Light from the sun reaches the Earth in 8.3min. The speed of light is 3.00x10g m/s. in kilometer, how far is the Earth from the sun?

d)An electron travels at a unifor velocity of 3.2x10g m/s, how much time is required for a displacement of 1.0m?

e)A person walks 5.0 km torwards the east in 2.0 hours,then 1.5 km towards the west in 0.5 hour, and finally 10.0 km torwards the east again in 2.25 hour. What is the person's average velocity?
 
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You need to show some attempt before anyone here can help you.

say_uri said:
a)A pool Cue exerted an average force of 160N on a cue ball over a distance of 0.012m How much work did the cue do on the ball.

b)If all the work done on (a) was transformed into kinetic energy of 0.0200kg cue ball, what was the speed of the ball?

What is the definition of work done and kinetic energy?

say_uri said:
c) Light from the sun reaches the Earth in 8.3min. The speed of light is 3.00x10g m/s. in kilometer, how far is the Earth from the sun?

How would you find distance given speed and time?

say_uri said:
d)An electron travels at a unifor velocity of 3.2x10g m/s, how much time is required for a displacement of 1.0m?

How do find time given distance and velocity?

say_uri said:
e)A person walks 5.0 km torwards the east in 2.0 hours,then 1.5 km towards the west in 0.5 hour, and finally 10.0 km torwards the east again in 2.25 hour. What is the person's average velocity?
What are the individual velocities for the journey?
 


well for a and b , i tried it. but i don't think it is correct.

a) w=f^d
w=160Nx0.012m
w=1.96

b) Ek=1/2mv2
i canceled , then ended up with √ 2x0.0200/1.92
V= 0.14433756729741

and for the rest of the questions i need help with the equations to use for.
c,d,and e
thanks
 


say_uri said:
b) Ek=1/2mv2
i canceled , then ended up with √ 2x0.0200/1.92
V= 0.14433756729741

You should have gotten

v = \sqrt{\frac{2E_k}{m}}

Check it again.

For c an d, if you multiply speed and time, what do you get?
 


for c,d and e.
C) i got 2490 km
8.3x30=2490

D)320 000 3.2x100 000

E)5.0x2.0=10
1.5x0.5=0.75
10.0x2.25=22.5

i don't know what to do next?
 


for b,
i calculated again , is this one right?
0.01041666666667
 


say_uri said:
for c,d and e.
C) i got 2490 km
8.3x30=2490

D)320 000 3.2x100 000

E)5.0x2.0=10
1.5x0.5=0.75
10.0x2.25=22.5

i don't know what to do next?
What are you using for the speed of light and the speed of the electron? I don't think you mean 'g' to be 9.81 m/s2

say_uri said:
for b,
i calculated again , is this one right?
0.01041666666667

Ek is the work done in part a).
 
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