A woman of mass 50 kg is swimming with a velocity of 1.6 m/s. If she stops stroking and glides to a stop in the water, what is the impulse of the force that stops her?
To find the impulse of the force that stops the woman while she is swimming, we can use the impulse-momentum principle. The impulse of a force is equal to the change in momentum of an object.
The momentum (p) of an object is given by the product of its mass (m) and velocity (v): p = m * v.
In this case, the woman's mass (m) is 50 kg and her initial velocity (v) is 1.6 m/s. We need to find her final velocity (vf) when she comes to a stop.
Since she stops stroking and glides to a stop, her final velocity (vf) is 0 m/s. The change in velocity (Δv) is then given by Δv = vf - vi = 0 - 1.6 = -1.6 m/s.
Now, we can calculate the impulse (J) of the force using the formula: J = m * Δv.
Substituting the known values, we get: J = 50 kg * (-1.6 m/s) = -80 kg·m/s.
The impulse of the force that stops the woman is -80 kg·m/s. The negative sign indicates that the direction of the impulse is opposite to her initial velocity.