# A skier(68 Kg) starts from rest but then begin to move downhill with a net force of 92N for 8.2 s. The hill levels out for 3.5 s. On this part of the...hill, net force on the skier is...

A skier(68 Kg) starts from rest but then begin to move downhill with a net force of 92N for 8.2 s. The hill levels out for 3.5 s. On this part of the...

hill, net force on the skier is 22N(backwards).

a). Calculate the speed of the skier after 8.2s?

b). Calculate the speed of the skier at the end of the section where the hill levels out?

c). Calculate the total distance travellled by the skier before coming to rest?

justaguide | College Teacher | (Level 2) Distinguished Educator

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The skier with a mass of 68 kg starts from rest. For 8.2 s the skier moves downhill and the net force on the skier is 92 N. The path then levels out and the skier moves for 3.5 s with a net opposing force of 22 N.

The acceleration of the skier in the initial 8.2 s is `92/68 = 23/17` m/s^2. As the initial speed is 0, the speed of the skier after 8.2 s is `0 + 8.2*(23/17) = 943/85 ~~ 11.09` m/s

The acceleration of the skier in the final 3.5 s is `22/68 = 11/34` m/s^2. The speed of the skier where the hill levels out is `0 + 8.2*(23/17) - 3.5*(22/68)` = `3387/340 ~~ 9.961` m/s

The total distance traveled by the skier before coming to a rest cannot be determined as the acceleration of the skier after duration of 11.7 s is not provided.