Arugby player of mass 75 kg, running east at 8.0 m/s, tackles another player of mass 90 kg who is running directly towards him at 5.0 m/s. if the two players cling together after the tackle, what will be their common velocity?

You can use the formula:
(m1 + m2)vf = m1vi
m1 = mass of first rugby player (75 kg)
m2 = mass of second rugby player (90)
vf = their final velocity
vi = the initial velocity 

(m1 + m2)vf = m1vi
(75 + 90)vf = (75)(8.0)
165(vf) = 600
        vf = 3.64 m/s

hope this helps :)

Aform of energy that is reflected or emitted from objects in the form of electrical and magnetic waves that can travel through space. there are many forms of  electromagnetic  energy including gamma rays, x rays, ultraviolet radiation, visible light, infrared radiation, microwaves and radio waves.

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