A toy machine gun fires 20 pellets at a target in one second and all the pettets are embedded in the target afterward. Suppose the mass of each pellet is 5 g and it leaves the gun at a speed of 10 m/s What is the average force exerted on the target?
1N
2N
3N
4N
f.4 physic
2007-06-18 6:01 am
回答 (2)
2007-06-18 6:06 am
✔ 最佳答案
Total mass of 20 pellets= 20m
= 20(0.005)
= 0.1 kg
Since in one second, there are 20 pellets embedded in the target.
So, by impulse = change of momentum
Ft = mv - mu
F = (m/t)(v - u)
F = (0.1)(0 - 10)
F = -1N
So, the average force exerted on the target is 1N.
參考: Myself~~~
2007-06-19 12:53 am
The sn unit of mass(M) In physics should be in kg.
By 1kg = 1000g
thus the mass of 20 pellets is 20x(5/1000)=0.1kg
By F=ma
Thus that F= (0.1)(10)
F=1N
By 1kg = 1000g
thus the mass of 20 pellets is 20x(5/1000)=0.1kg
By F=ma
Thus that F= (0.1)(10)
F=1N
收錄日期: 2021-04-12 19:56:57
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