Question

Help please

Answer 1

@Vocaloid

Answer 2

D

Answer 3

yup good

Answer 4

D

Answer 5

good

Answer 6

D

Answer 7

yup good

Answer 8

B

Answer 9

good

Answer 10

A

Answer 11

Hm. I think that's correct (some KE was lost but not all of it)

Answer 12

hint: momentum is conserved

Answer 13

conservation of momentum: initial momentum = final momentum (for the system)

so change in momentum = ?

Answer 14

1100

Answer 15

that's the mass

change in a physical quantity or state = final - initial

for conserved momentum , final momentum - initial momentum = ?

Answer 16

if final momentum = initial momentum

final momentum - initial momentum = ?

Answer 17

as a hint this problem can be solved w/o using any of the numbers in the problem

Answer 18

if A = B

then B - A = 0 since something minus itself is 0

so final momentum - initial momentum = 0 (C)

since initial and final momentum are equal, there is no change in momentum

Answer 19

final momentum = initial momentum

so simply calculate the total momenta of the two cars, taking into account they're going in opposite directions so their momenta will partly cancel out

Answer 20

Um C

Answer 21

what's the momentum of the car going north?

Answer 22

momentum = mv = ?

Answer 23

39000

Answer 24

good, wb the car going south?

Answer 25

and then 13500

Answer 26

good, and 39000 - 13500 = ?

Answer 27

B

Answer 28

the result is positive, so the net momentum has to be north (D)

Answer 29

Right thanks

Answer 30

C

Answer 31

good

Answer 32

C

Answer 33

good

Answer 34

initial momentum of cannon + initial momentum of water balloon = final momentum of cannon + final momentum of water balloon

0 + 8(1) = 5(v) + 0

solve for v

Answer 35

8/5

Answer 36

A

Answer 37

since the launcher gets knocked back in the opposite direction of the balloon in needs tobe west (d)

Answer 38

C

Answer 39

energy is ~always~ conserved (they're not just talking about kinetic energy here, all types of energy)

so D is the better option

Answer 40

B

Answer 41

in the beginning there's one puck going 8 m/s east and one puck going 7 m/s west

since the pucks are equal in mass, if one puck is going 7 m/s west, the other puck has to be going 8 m/s east (D) to create the same momenta we had before

Answer 42

note: this only works b/c the pucks are equal in mass, otherwise this trick wouldn't work

Answer 43

Got it

Answer 44

elastic (kinetic energy is conserved, so it doesn't get converted to anything) just have to memorize this

Answer 45

Thank you so much for all your help