# Kids in a Sled

Pro Problems > Physics > Motion and Forces > Linear Motion > Force > Friction > Kinetic Friction## Kids in a Sled

Willy (m = 15 kg) and Jill (m = 10 kg) are riding on a sled (m = 5 kg). I am pulling them just hard enough to give them a constant speed of 5 m/s on a horizontal surface. The coefficient of friction between the sled and the snow is 0.08. Willy jumps out of the sled, and I continue pulling with the same force. How long will it take Jill and the sled to travel 50 more meters after Willy jumps out of the sled?

## Solution

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