I need help with physics!!!

[RoOkaYya G]

Can anyone help me with physics?

P.S i may ask dumb questions too coz my brain isnt working these days.so plz bear with me.
Thank u.

 

[MemoryMatrix 21]

ask ?? what's our doubt ?? i'll try

 

[RoOkaYya G]

when do we use the minus sign for the equation GMm/r ?

 

[MemoryMatrix 21]

we use it when we are finding gravitational potential !!
Why gravitational potential values are always negative?
- As the gravitational force on the mass is attractive, the work done by an ext agent in bringing unit mass from infinity to any point in the field will be negative work{as the force exerted by the ext agent is opposite in direction to the displacement to ensure that KE = 0}
- Hence by the definition of negative work, all values are negative.

 

[MemoryMatrix 21]

Can anyone help me with physics?

P.S i may ask dumb questions too coz my brain isnt working these days.so plz bear with me.
Thank u.

no prb
hope that helps

 

[RoOkaYya G]

no prb
hope that helps

thank u so so much! ^_^ indeed it helped!
ive to complete 8 papers per day for 7 days in all! :/

 

[MemoryMatrix 21]

thank u so so much! ^_^ indeed it helped!
ive to complete 8 papers per day for 7 days in all! :/

no prb
bst of luck

 

[Thought blocker]

Physics and Math help our brain to be fresh, Love both of em

 

[RoOkaYya G]

i used to love physics now im like "wtf" whn i see a phys paper

 

[Thought blocker]

LOL Rookz

 

[Waqas Nasir]

i used to love physics now im like "wtf" whn i see a phys paper

Thats why u hate exams lol. Btw i love physics!!

 

[RoOkaYya G]

Thats why u hate exams lol. Btw i love physics!!

help me then

 

[Thought blocker]

help me then

Ask fast, I am leaving

 

[RoOkaYya G]

Ask fast, I am leaving

nothing to ask for now kiddo.thnks for the concern ^_^

 

[Thought blocker]

Anytime rookz

 

[RoOkaYya G]

Anytime rookz

sweet kiddo ^_^

 

[RoOkaYya G]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s07_qp_4.pdf Qu 3 part b

Thought blocker Waqas Nasir

 

[RoOkaYya G]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s08_qp_4.pdf Qu 1 part b

Thought blocker Waqas Nasir @
♣♠ Magnanimous ♣♠

 

[A star]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s08_qp_4.pdf Qu 1 part b

Thought blocker Waqas Nasir @
♣♠ Magnanimous ♣♠

dw it gets worst as the year progresses gravitational energy is basically the chapter that is supposed to be a mark gainer
you know F is the centripetal force. and you need to find out revolutions per minute which is basically omega so you can equate
Mr(omega)^2=0.72W
W=Mg so
Mr(omega)^2=0.72*9.81245M
cancel M on both sides
now r is d so it is equal to 35 cm or 0.35 m
now equate to find omega
after you have found omega use the formulae
omega=2(pie)/T and rearrange it to form
1/T=omega/2pie and multiply by 60 to get the ans in minutes

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s08_qp_4.pdf Qu 1 part b

Thought blocker Waqas Nasir @
♣♠ Magnanimous ♣♠

1b)
frictional force=centripetal force since friction provides the centripetal force
For example suppose that a driver of a car makes a sharp turn to the left of a road or u can say a turn about at constant speed. During the turn, the car travels in a circular-type path. That is, the car sweeps out one-quarter of a circle. The friction force acting upon the turned wheels of the car causes an unbalanced force upon the car and a subsequent acceleration. The unbalanced force and the acceleration are both directed towards the center of the circle thus making the car adopt a circular path.So as u can see its the friction thats causing the car to move in circular path meaning its providing the centripetal force.IF IT werent for friction the car wouldnt have been able to make a turn and would have gone straight.