Question

Jennifer, who has a mass of 40.0 kg, is riding at 25.0 m/s in her red sports car when she must suddenly slam on the brakes to avoid hitting a deer crossing the road. She strikes the seat belt, that brings her body to a stop in 0.400 s. What average force does the seat belt exert on her?

Answer 1

Answer:

The seat belt exert an average force of 2500 N on Jennifer

Explanation:

Force: Force can be defined as the product of mass and acceleration/deceleration. The S.I unit of force is Newton (N). Mathematically it is expressed as

Force(F) = Mass(m) × deceleration(d)

F = md................... Equation 1

But,

Deceleration: Acceleration can be defined as the rate of change of velocity.

mathematically it can be represented as,

d = u-v/t (deceleration).................. Equation 2

Where v = final velocity, u = initial velocity, t = time.

Given: u= 25 m/s, v = 0 m/s, t = 0.4 s.

Substituting these values into Equation 2

d = (25-0)0.4

d = 62.5 m/s²

Also given: m = 40.0 kg. and d = 62.5 m/s²

Substituting these values into equation 1,

F  = 40×62.5

F = 2500 N

The seat belt exert an average force of 2500 N on Jennifer