4/7/2015
Chapter 10
Page 509
#35,36,37
35.A 0.150kg billiard ball (A) is rolling toward a stationary billiard ball (B) at
10.0 m/s. After the collision, ball A rolls off at 7.7 m/s at an angle of 40.0°
clockwise from its original direction. What is the speed and direction of
ball B after the collision
v
PA = m Av A = (0.150kg )(10.0 ms ) = 1.50 kgs⋅m
v
PB = mB vB = (0.150kg )(0.0 ms ) = 0 kgs⋅m
v
v )
)
PA = P j A = 1.50 j kgs⋅m
i
j
A
0
1.50
B
0
0
Total
0
1.50
0
1.50
A’
B’
Total’
1
4/7/2015
35.A 0.150kg billiard ball (A) is rolling toward a stationary billiard ball (B) at
10.0 m/s. After the collision, ball A rolls off at 7.7 m/s at an angle of 40.0°
clockwise from its original direction. What is the speed and direction of
kg ⋅m
ball B after the collision v
m
40.0°
PA ' = m Av A ' = (0.150kg )(7.7 s ) = 1.155 s
v
v
PA ' iˆ = sin θ ( PA ' )
v
PA ' iˆ = sin( 40.0°)(1.155 kgs⋅m ) = 0.7424 kgs⋅m
v )
PA ' j = cos(40.0°)(1.155 kgs⋅m ) = 0.8848 kgs⋅m
1.155 Kg m/s
i
j
A
0
1.50
B
0
0
Total
0
1.50
A’
0.7424
0.8848
0
1.50
iˆ
)
j
B’
Total’
i
j
A
0
1.50
B
0
0
Total
0
1.50
A’
0.7424
0.8848
B’
-0.7424
0.6152
Total’
0
1.50
v
)
ˆ > +0.6152 kgm < j >
PB ' = −0.7424 kgm
<
i
s
s
Use Pythagoras theorem to solve
v
2
PB ' = − 0.7424 kgm
+ 0.6152 kgm
s
s
v
PvB ' = 0.9642 kgm
s
PB ' = mB vB ' = 0.9642 kgm
s
(
P[j]
P[i]
vB ' =
) (
0.9642 kgm
s
= 6.43 ms
0.150kg
)
2
θ = tan −1 00..7424
= 50.4°
6152
N 50.4°W
2
4/7/2015
36. A bowling ball with a mass of 6.00kg rolls with a velocity of 1.20 m/s
toward a single standing bowling pin that has a mass of 0.220kg. When the
ball strikes the bowling pin, the pin flies off at an angle of 70.0°
counterclockwise from the original direction of the ball with a velocity of
3.60 m/s, What was the velocity of the bowling ball after it hit the pin?
36. A bowling ball with a mass of 6.00kg rolls with a velocity of 1.20 m/s
toward a single standing bowling pin that has a mass of 0.220kg. When the
ball strikes the bowling pin, the pin flies off at an angle of 70.0°
counterclockwise from the original direction of the ball with a velocity of
3.60 m/s, What was the velocity of the bowling ball after it hit the pin?
3
4/7/2015
37. Car A (1750 kg) is travelling due south and car B (1450kg) is travelling due
east. They rach the same intersection at the same time and collide. The
cars lock together and move off at 35.8 km/hr [E 31.6°S]. What was the
velocity of each car before they collided?
4
4/7/2015
37. Car A (1750 kg) is travelling due south and car B (1450kg) is travelling due
east. They reach the same intersection at the same time and collide. The
cars lock together and move off at 35.8 km/hr [E 31.6°S]. What was the
velocity of each car before they collided?
5