On newton law of motion?
2016-08-02 10:27 am
A body of mass 50kg running at 5 m/sec jump on to a 20kg trolley traveling in the same direction at 1.5 m/sec . What is their common velocity ?
回答 (2)
2016-08-02 10:33 am
Total momentum before the body jumps on to the trolley
= 50 × 5 + 20 × 1.5 kg m/s
Total momentum after the body jumps on to the trolley
= (50 + 20) × v (kg m/s)
The conservation of momentum :
50 × 5 + 20 × 1.5 = (50 + 20) × v
70v = 280
Common velocity, v = 4 m/s
= 50 × 5 + 20 × 1.5 kg m/s
Total momentum after the body jumps on to the trolley
= (50 + 20) × v (kg m/s)
The conservation of momentum :
50 × 5 + 20 × 1.5 = (50 + 20) × v
70v = 280
Common velocity, v = 4 m/s
2016-08-02 2:45 pm
momentum I = I1+I2 is conserved
I1 = 50*5
I2 = 20*1.5
I = 250+30 = 280 kg*m/sec
V = I/(50+20) = 280/70 = 4.0 m/sec
I1 = 50*5
I2 = 20*1.5
I = 250+30 = 280 kg*m/sec
V = I/(50+20) = 280/70 = 4.0 m/sec
收錄日期: 2021-04-18 15:23:11
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20160802022719AAg5uw1