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timels
a hot air balloon is released and it accelerates upwards. during the ascent, some sandbags are released and
the acceleration increases. the graph shows its vertical motion during the first 50 seconds of its flight.
speed/ms
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time/s
) calculate the acceleration after the sandbags are released.
) how high had the balloon risen after the 50 seconds had passed?
20 september, 2019

the design of a ski jumping suit involves a trade-off between giving the skiers lift to get higher jumps and ensuring the skier does not face a lot of drag before the jump itself. an expansive suit may to lift the skier higher, but at the same time, it will also increase the air resistance. higher air resistance as the skier goes down the slope limits the speed of the jump. a big suit also increases the risk of losing balance or control, especially if there's a strong gust of wind. while technologically enhanced suits a lot, clothing is not the only factor in a ski jumper’s success. gathering speed while skiing down the slope, ensuring good speed on the ramp, and maintaining good body posture and form in the air all contribute to a ski jumper's success.

the answer is c. the lower legs are levers, and the knees are fulcrums. the ankles hold the loads.