Question

An ice skater is gliding horizontally across the ice with an initial velocity of 7.56 m/s. The coefficient of kinetic friction between the ice and the skate blades is 0.0695, and air resistance is negligible. How much time elapses before her velocity is reduced to 2.32 m/s

Answer 1

Answer:  7.723s

Explanation:

given data:

initial velocity = 7.56 m/s.

friction = 0.0695.

change in velocity = 2.32 m/s

Solution:

$ax = \frac{-Fk}{m}$

$ax = \frac{-ukFN}{m}$

$ax = \frac{-ukmg}{m}$

$ax = -ukg$

$recall = v0x +axt$$.......eqn1$

$t = \frac{vx - v0x}{ax}$ $........eqn2$

$substitute$  $ax$  $into$  $eqn 2$

$t = \frac{vx -v0x}{-ukg}$

$t = \frac{2.32m/s - 7.56m/s}{-(0.0695)(9.80m/s^{2})}$

$t= 7.723seconds$