There are only two things you can do to increase the work output of a machine:
1). Increase the work INput to the machine.
2). Make the machine more efficient ... do things like lubricating it better to eliminate some internal friction.
Velocity =displacement
Change in time
D=72km/hr
Time=20s
But the S.I unit of velocity is m/s so you woul have to change 72km/hr to m/s
Changing 72km to m
1 kilometer=1000meters
Then, 72 kilometers =?
72•1000/1
=72000m
Changing 72hours to seconds
If 1 hour = 3600 seconds
Then 72 hours=?
72•3600/1
=259200 seconds
Velocity =displacement
Change in time
V= 72,000
259,2005
=0.028m/s
The colors that you see on the CD are created by white light reflecting from ridges in the metal. When light reflects off or passes through something with many small ridges or scratches, you often get rainbow colors and interesting patterns. They are called interference patterns.
The momentum p of a moving particle is the product between its mass, m, and tis velocity, v:

In our problem, we know

and

, and using the relationship mentioned above, we can find the mass m of the particle:
Answer:
A compound
Explanation:
A compound is a substance formed when two or more elements are chemically joined