Question

Calculate the final speed (in m/s) of a 104 kg rugby player who is initially running at 7.75 m/s but collides head-on with a padded goalpost and experiences a backward force of 1.85 ✕ 104 N for 7.00 ✕ 10⁻² s

Answer 1

The final speed of the rugby player is approximately -169.25 m/s.

Step-by-step explanation:

To calculate the final speed of the rugby player, we can use the equation:

V_f = V_i + (F / m) * t

where:

V_f is the final velocity

V_i is the initial velocity

F is the force

m is the mass

t is the time

Plugging in the given values:

V_i = 7.75 m/s

F = -1.85 × 10^4 N

m = 104 kg

t = 7.00 × 10^-2 s

Using these values in the equation:

V_f = 7.75 + (-1.85 × 10^4 / 104) * 7.00 × 10^-2

Simplifying the equation:

V_f = 7.75 - 1.77 × 10^2

V_f ≈ -169.25 m/s

Therefore, the final speed of the rugby player is approximately -169.25 m/s.