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10 votes
10 votes
Question 2 of 10

An 85.0 kg man playing hockey catches a puck moving at 25.0 m/s. The man
is initially at rest. The man and the puck move together after the collision. The
puck's mass is 0.16 kg. What is the final velocity?
A. 0.05 m/s
B. 13.6 m/s
C. 4.00 m/s
D. 1.00 m/s
SUBMIT

User Grigb
by
2.8k points

1 Answer

22 votes
22 votes

Step-by-step explanation:

Using the law of the conservation of linear momentum P:

P_i = P_fP

i

=P

f

so:

M_mV_{mi}+M_pV_{pi} = M_sV_sM

m

V

mi

+M

p

V

pi

=M

s

V

s

where M_mM

m

is the mass of the man, V_{mi}V

mi

is the initial velocity of the man, M_pM

p

is the mass of the puck, V_{pi}V

pi

is the initial velocity of the puck, M_sM

s

is the mass of the puck and the man and V_sV

s

is the velocity of both after the collition.

Replacing values, we get:

(80kg)(0m/s)+(0.17kg)(20m/s) = (80kg + 0.17kg)V_s(80kg)(0m/s)+(0.17kg)(20m/s)=(80kg+0.17kg)V

s

Finally, solving for V_sV

s

:

V_sV

s

=0.0424m/s

User Abhisekp
by
2.7k points