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A roller coaster starts with a speed of 4.6 m/s at a point 49 m above the bottom of a dip.

Neglecting friction, what will be the speed of the roller coaster at the top of the next
slope, which is 29 m above the bottom of the dip?

User Hvollmeier
by
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1 Answer

4 votes

Answer:

20.5m/s

Step-by-step explanation:

neglecting friction the amount of energy at the bottom equals to the amount of energy at top. Law of conservation of energy.

ME= P.E+k.E

ME= mgh+ 1/2mv*v

ME = (m* 10 *49)+(1/2m(4.6*4.6))

MEtop=500.98m

MEbottom=MEtop: in order to obey the law of conservation of energy

MEbottom=mgh+ 1/2mv*v

500.98m=m*10*29+1/2m v* v

500.98m= m(290+1/2v*v) ...cancel m by m

500.98-290=1/2v*v criss cross multiple

210.98*2=v*v

v=√421.96

v=20.5 m/s

User Sanjay Singh Rawat
by
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