Sorry im from the UK, ill do my math in metric :)
5) work done = force * distance moved in direction of force
170J = 140N* ?d
170J/140N = 1.21m
F=Ma
140N/9.81ms^-2=
14.27Kg or 31.46Ib
you could do the fast alternative simplified route to this question
as 140/4.45 = 31.46Ib
Answer:
The distance covered by puck A before collision is 
Explanation:
From the question we are told that
The label on the two hockey pucks is A and B
The distance between the two hockey pucks is D 18.0 m
The speed of puck A is 
The speed of puck B is 
The distance covered by puck A is mathematically represented as

=> 
The distance covered by puck B is mathematically represented as

=> 
Since the time take before collision is the same

substituting values

=> 
=> 
Each person is 80kg. 320/4
Answer:
Efficiency can be increase by using rollers in conjunction with the inclined plane. Wedge. The wedge is an adaptation of the inclined plane. It can be used to raise a heavy load over a short distance or to split a log