What is Billie's speed after pushing off Joannie in the parking lot?~~

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Billie's speed after pushing off Joannie in the parking lot is approximately 20 ft/s. Joannie moves at a constant speed of 14 ft/s, which converts to 4.27 m/s. Using the conservation of momentum and the formula a=F/m, Billie's acceleration is calculated to be 6.1 m/s. This acceleration is then converted to feet per second, confirming Billie's speed as 20 ft/s. Consequently, Billie moves faster than Joannie due to her lower mass, resulting in greater acceleration from the same force.
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Billie (35 kg) and Joannie (50 kg), both with brand new roller blades, are at rest facing each other in the parking lot. They push off each other and move in opposite directions, Joannie moving at a constant speed of 14 ft/s. What speed is Billie moving?

Joanie: convert ft/s to meters 14ftx12 in=168in. 168/39.37=4.27 meters
a=F/m 4.27m=F/50kg
F=213.5 N

Billie: a=213.5 kgm/35kg
a=6.1m

6.1m x 39.37 in= 240in
240in/12in= 20ft/s
 
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jatwood1977 said:
Billie (35 kg) and Joannie (50 kg), both with brand new roller blades, are at rest facing each other in the parking lot. They push off each other and move in opposite directions, Joannie moving at a constant speed of 14 ft/s. What speed is Billie moving?
Use Conservation of Momentum to obtain:
{Mass of B}*{Speed of B} = {Mass of J}*{Speed of J}


~~
 
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Based on the given information, Billie's speed after pushing off Joannie in the parking lot is approximately 20 ft/s. This is calculated by using the formula a=F/m, where a is the acceleration, F is the force, and m is the mass. First, we need to convert Joannie's speed from feet per second to meters per second, which is 4.27 m/s. Then, using the same formula, we can calculate the acceleration of Billie, which is 6.1 m/s. Finally, we can convert this acceleration to feet per second, which gives us a speed of 20 ft/s. This means that Billie is moving at a faster speed than Joannie, as expected since she has a lower mass and therefore experiences a greater acceleration from the same force.
 

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