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solmaris [256]
3 years ago
8

A person slaps her leg with her hand, which results in her hand coming to rest in a time interval of 2.65 ms from an initial spe

ed of 5.25 m/s . What is the magnitude of the average contact force exerted on the leg, assuming the total mass of the hand and the forearm to be 1.75 kg
Physics
1 answer:
dezoksy [38]3 years ago
5 0

Answer:

the magnitude of the average contact force exerted on the leg is  3466.98 N

Explanation:

Given the data in the question;

Initial velocity of hand v₀ = 5.25 m/s

final velocity of hand v = 0 m/s

time interval t = 2.65 ms = 0.00265 s

mass of hand m = 1.75 kg

We calculate force on the hand F_{hand

using equation for impulse in momentum

F_{hand × t = m( v - v₀ )

we substitute

F_{hand × 0.00265  = 1.75( 0 - 5.25 )

F_{hand × 0.00265  = 1.75( - 5.25 )

F_{hand × 0.00265  = -9.1875

F_{hand = -9.1875 / 0.00265  

F_{hand = -3466.98 N

Next we determine force on the leg F_{leg

Using Newton's third law of motion

for every action, there is an equal opposite reaction;

so, F_{leg = - F_{hand

we substitute

F_{leg = - ( -3466.98 N )

F_{leg = 3466.98 N

Therefore, the magnitude of the average contact force exerted on the leg is  3466.98 N

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