• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

I am repeating my As level.

Thought blocker

Thought blocker

Messages
8,477
Reaction score
34,837
Points
698
dumb human said:
Thought blocker MAN PLZ EXPLAIN QUESTION 9.. OCT/NOV/PHYSICS
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_12.pdf
Click to expand...
dumb human said:
A

And Q)13 Too :/
Click to expand...
9)
force=rate of change of momentum
60=-(30v-30*3)/0.5 (i put a minus sign before the bracket because the force is a retarding force, so the acceleration will be negative)
v= 2

13)
assuming it is projected with velocity v, so the initial KE, E= (mv^2)/2
at the highest point, the vertical component of the veolcity = 0, so its left with v cos 45,
so final KE = 1/2 x m x (v cos 45)^2 = 0.5E
 
dumb human

dumb human

Messages
338
Reaction score
868
Points
93
Thought blocker said:
9)
force=rate of change of momentum
60=-(30v-30*3)/0.5 (i put a minus sign before the bracket because the force is a retarding force, so the acceleration will be negative)
v= 2

13)
assuming it is projected with velocity v, so the initial KE, E= (mv^2)/2
at the highest point, the vertical component of the veolcity = 0, so its left with v cos 45,
so final KE = 1/2 x m x (v cos 45)^2 = 0.5E
Click to expand...
i did 9th one the same way...but i get 4..... :/
and i tried 13th one your way.....but i get 0.71 :(
 
Thought blocker

Thought blocker

Messages
8,477
Reaction score
34,837
Points
698
dumb human said:
i dont knw question 14 and 15 also ......
Click to expand...
14)
By conservation of momentum, 2 x 2 = 1 x v, v =4
so the 1kg trolley moves 4ms-1 to the right,
calculating the total KE of the both trolleys, which is 1/2 x 2 x 2^2 + 1/2 x 1 x 4^2 = 12J
assuming no energy is lost, the energy stored in the spring is converted to KE gained by the trolleys, so its 12J

15)
Show me your workings... its easy.
 
A

A star

Messages
2,703
Reaction score
3,939
Points
273
God you guys are confsed over uncertainites like this in As what will happen in A2s when the whole world of uncertainities will change :p

Thought blocker said:
14)
By conservation of momentum, 2 x 2 = 1 x v, v =4
so the 1kg trolley moves 4ms-1 to the right,
calculating the total KE of the both trolleys, which is 1/2 x 2 x 2^2 + 1/2 x 1 x 4^2 = 12J
assuming no energy is lost, the energy stored in the spring is converted to KE gained by the trolleys, so its 12J

15)
Show me your workings... its easy.
Click to expand...
ur questions are answered by now i guess?
 
dumb human

dumb human

Messages
338
Reaction score
868
Points
93
Thought blocker said:
14)
By conservation of momentum, 2 x 2 = 1 x v, v =4
so the 1kg trolley moves 4ms-1 to the right,
calculating the total KE of the both trolleys, which is 1/2 x 2 x 2^2 + 1/2 x 1 x 4^2 = 12J
assuming no energy is lost, the energy stored in the spring is converted to KE gained by the trolleys, so its 12J

15)
Show me your workings... its easy.
Click to expand...


i got 14 now...but i dont knw how to do 15.. should i do, I=P/V ?
 
You must log in or register to reply here.
Top