Jocko has a mass of 95kg. He stands at rest on ice and catches a 7kg ball thrown at 6km/hour. How fast does Jocko and the
ball move across the ice after he catches it?
I think the answer is .41km/hour and my friend thinks its .5km/hour. What do you think the correct answer is?
PLEASE SHOW WORK, if possible. Thanks.
2006-10-06 02:04:39 · 4 answers · asked by eternal.diamonds 1 in Education & Reference ➔ Homework Help
Momentum = Mass x Velocity
Momentum is constant
Therefore momentum of ball = 7 x 6 = 42kgkm/h
Momentum of Jacko and ball = 42kgkm/h
Mass of Jacko and ball = 102kg
Therefore Velocity of Jacko and ball = 42/102 = .41km/h
So yes you are Correct!
2006-10-06 02:11:11 · answer #1 · answered by Rich 1 · 0⤊ 0⤋
We must assume that we are ignoring friction since Jocko is standing on ice.
The formula is:
M1V1 = M2V2
M1 = Mass of object 1 = 7 kg
V1 = Velocity of object 1 = 6 kmh
M2 = Mass of object 2 = (7+95) = 102 kg
v2 = Unknown
7*6 = 102*V2
V2 = 42/102
V2 = 0.41 km/h
2006-10-06 09:16:10 · answer #2 · answered by T 5 · 0⤊ 0⤋
The energy is put into a 7 KG ball. If he catches it he becomes a 102KG object with almost the same energy.
6 km/hour for 7 kg becomes..... x km/hour for 102 kg.
Lets make it easy and just do the basic math.
0.41 km/hour is the correct answer. Your friend thinks the ball is 'for free'. It is not.
2006-10-06 09:08:26 · answer #3 · answered by Puppy Zwolle 7 · 0⤊ 0⤋
f=ma
f=6*7=42
42=95*x
42/95 = .44kph
assuming coeff stat fric = o
assuming complete transfer of all of ball's energy to Jocko
2006-10-06 09:12:35 · answer #4 · answered by Anonymous · 0⤊ 0⤋