Linear momentum (mass x speed) has to be conserved.
-- Momentum before the jump:
(boy's mass) x (boy's speed) = (25 kg) x (4.0 m/s) = 100 kg-m/s
(cart's mass) x (cart's speed) = (15 kg) x (zero) = zero
Total momentum before the jump: (100 kg-m/s) + (zero) = (100 kg-m/s)
-- Momentum after the jump:
(mass of boy+cart) x (speed of boy+cart) = (40 kg) x (speed)
-- Momentum after the jump = momentum before the jump
(40 kg) x (speed) = 100 kg-m/s
Divide each side by 40 kg:
Speed = (100 kg-m/s) / (40 kg)
<em>Speed = 2.5 m/s</em> (d)
The author's best argument against the light-rail project is that it is unnecessary. A combination of trams characterizes light rail transit, a type of passengers urban rail transportation.
<h3>What does light rail accomplish?</h3>
In big cities, LRT can function as an independent organization or as a complement to heavy rail and passenger rail systems. The fastest and most economical interurban transport in a city is provided by LRT.
<h3>What does light rail accomplish?</h3>
Heavy rail systems can be supplemented by LRT, and commuter rail networks in big cities can function independently. In a metropolitan area, LRT offers the fastest and most affordable interurban transportation service. It is intended to close a considerable gap between light rail and local buses.
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<span> The concentration of the substance is greater outside the cell than inside.</span>