The ice skater's record was 500 m with an average of 12.92 m/s. Suppose she crossed a finish line at this speed and came to a stop. If the work done by friction over a certain distance was -2830 J, what would her kinetic energy be, assuming her mass is 55 kg.
2006-12-11 16:29:51 · 2 answers · asked by maggie 1 in Science & Mathematics ➔ Physics
The initial KE is mv^2/2 = 4590 J
After travelling the "certain distance" the KE is
4590J - 2830J = 1760 J
The total energy is conserved. The initial KE is converted to heat by the friction force.
2006-12-11 17:30:13 · answer #1 · answered by d/dx+d/dy+d/dz 6 · 0⤊ 0⤋
hi. The skater will decelerate as she travels. area of that's air resistance, area is that the skate motives the ice to soften somewhat and some ability is lost as warmth. there is continually friction on mechanical surfaced which contact.
2016-11-25 22:11:16 · answer #2 · answered by stockbridge 4 · 0⤊ 0⤋